Multi-Family Homes for Sale: A Smart Path to Real Estate Wealth

# Multi-Family Homes for Sale: The Operator's Framework for Evaluating Income Property

You've held single-family rentals for a few years. The returns are fine — 5%, maybe 6% on a good year — but every renewal cycle feels like running uphill. One vacancy wipes out a quarter's cash flow. One bad furnace eats the year. You're looking at the next property and asking whether stacking another single-family unit makes sense, or whether the answer is changing the structure of what you own entirely.

That's the right question. The buyers who outperform aren't the ones who find better deals — they're the ones who change the asset class. Multi family homes for sale sit in a different mathematical category than single-family rentals: different financing, different tenant math, different exit options. Investors evaluating Boca Raton Real Estate often start here, because the 2–4 unit threshold is where residential financing still works but income properties begin to behave like businesses.

What follows is a working framework — financing first, tenant math second, exit third — for evaluating the next property you look at the way an experienced operator would.

Table of Contents

• Why Multi-Family Returns Outpace Single-Family
• Ownership Structures That Decide Your Real Return
• The Due Diligence Checklist That Stops Six-Figure Mistakes
• Reading the Market: Listable vs. Lendable
• Financing Levers That Multiply or Vaporize Returns
• The Offer and Negotiation Playbook
• Deal-Killers Between Contract and Close
• Your Live-Deal Evaluation Template

Why Multi-Family Returns Outpace Single-Family

Most buyers conflate two ideas that should be separated immediately: gross return and risk-adjusted return. Single-family rentals advertise 5–8% cash-on-cash returns in stabilized markets. Multi-family properties of 2–4 units often run 7–11%, not because the rents are higher per unit, but because operating costs spread across multiple rent rolls and vacancy risk dilutes mathematically.

There are four mechanical reasons this works.

Vacancy math is the first. On a single-family rental, one vacancy equals 100% income loss for that month. On a 4-unit building, one vacancy equals 25% income loss. A duplex with one tenant out still services half the mortgage. A single-family house with the tenant out services zero. Lenders price this resilience directly into debt-service coverage ratio (DSCR) requirements, which is why multi-family loans often allow tighter DSCR thresholds — commonly 1.20–1.25x — than commercial deals on single-tenant properties.

Economies of scale on operating costs is the second. One roof covers four units instead of one. One landscaper services one address. Insurance is bundled into a single policy. Property management fees, while sometimes higher in percentage terms (8–10% versus 6–8% on single-family), produce lower per-unit overhead because the manager handles one site visit, not four. The math on per-unit expense is what compounds — not the headline percentage.

The rental income from four units absorbs a single vacancy far better than one property does, and lenders price that resilience directly into your loan terms.

Financing structure is the third, and it's the single most consequential variable. Properties of 2–4 units still qualify for residential conventional financing through Fannie Mae and Freddie Mac. That means 30-year fixed rates, lower down payments (as low as 15–25% for non-owner-occupied), and standard credit underwriting based on personal income. The buyer is treated as a homeowner who happens to live next door to the tenants — or doesn't live there at all but operates within the residential framework. Buying a Duplex for Sale sits squarely inside this favorable financing window.

Properties of 5+ units cross into commercial loan territory. Shorter amortization (often 20–25 years), balloon payments at year 5 or 10, and DSCR-based underwriting rather than personal income. The borrower's W-2 becomes largely irrelevant; the property's income does the qualifying. This 4-vs-5 unit threshold is the single most important number in multi-family financing, and most buyers don't understand its weight until they're already under contract on a 5-unit and discovering what a balloon payment actually means.

Cap rate framework is the fourth. Capitalization rate is Net Operating Income divided by Purchase Price. A property generating $60,000 NOI bought at $750,000 trades at an 8% cap. Cap rate is the right metric for multi-family but useless for single-family. Single-family is comp-driven — price per square foot versus recent sales. Multi-family is income-driven. A buyer paying above market cap rate is paying for upside they have to create themselves through operations.

The skeptic's objection is real: isn't this concentrated risk? Four units in one building, one roof, one neighborhood, one local employer base. The answer is that concentration risk is real if you buy in a single-employer town or a single-demographic submarket. But the building itself is a diversifier, not a concentrator, because it holds multiple income streams under one roof. The risk is in the submarket selection, not the structure.

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Ownership Structures That Decide Your Real Return

Buying a multi-family property actually means choosing between four structures, and the structure changes your return more than the property itself does. Two buyers can purchase the same 4-plex and end up with 12% and 4% cash-on-cash returns depending on how they hold it.

Structure	Capital Required	Time to Cash Flow	Control Level	Exit Flexibility
Direct, 2–4 units (residential)	15–25% down	30–60 days	Full	Sell anytime, 1031 eligible
Direct, 5+ units (commercial)	25–35% down	60–120 days	Full	Balloon refi at year 5–10
Syndication (LP position)	$50K–$250K min	6–18 months	None operationally	Locked 5–7 years typical
Tenant-in-common (TIC)	Varies by share	30–90 days	Shared	Co-owner consent required
Seller financing / wraparound	10–20% down possible	30 days	Full	Constrained by seller's note

Direct ownership of 2–4 units is the default for the operator-investor. Full control, residential financing, manageable scale, and an exit path that doesn't depend on anyone else's calendar. This is where most successful multi-family portfolios begin.

Direct ownership of 5+ units forces a commercial loan, which means balloon-payment risk every 5–10 years and refinance exposure to whatever rate environment exists at that moment. The math at purchase can be excellent; the math at refinance can destroy the position if rates have moved against you. Buyers who acquired 5+ unit properties in 2020–2021 at 3.5% rates are encountering this reality now as their balloons approach.

Syndication trades control for passivity. The limited partner writes a check, receives distributions, and loses any say in dispositions, financing decisions, or timing. For investors who want exposure to the asset class without operating responsibilities — and who trust the sponsor — this is a legitimate vehicle. For investors who believe they can manage better than they can pick managers, it's a wealth transfer.

TIC structures are rare but useful when two operators bring complementary capital — one with cash, one with operational expertise. Seller financing is the most underused option in the entire category. When sellers carry paper, buyers get lower closing costs, faster timelines, and negotiating leverage on price because the seller becomes economically tied to the property's continued performance. Sellers who finance want the buyer to succeed.

The framing question every buyer should answer before looking at a single listing: are you buying a business (direct, 2–4 units), an asset class allocation (syndication), or a tax structure (5+ commercial with cost segregation)? The answer changes everything that follows — what you look at, how you finance, who you hire, how you exit.

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The Due Diligence Checklist That Stops Six-Figure Mistakes

The boilerplate inspection list misses what actually kills multi-family deals. Below is the checklist senior brokers run, item by item, with what failure looks like in each case.

1. Roof age and remaining life. Get the original install date and any partial replacements. A 25-year shingle roof at year 22 on a 4-plex is a $15K–$30K liability you absorb at closing if you don't price it in. Ask for the roofing invoice, not just the seller's recollection.
2. HVAC inventory by unit. Multi-family buildings often have mixed HVAC ages because units were renovated in waves. Catalog each unit's system age, type (central vs. window vs. mini-split), and last service date. A building with four 18-year-old condensers is one bad summer from $20K in emergency replacements that the seller's pro forma never mentioned.
3. Electrical panel capacity and type. Federal Pacific and Zinsco panels are uninsurable in many markets. Aluminum branch wiring triggers insurance surcharges or outright denial. Verify amperage capacity matches modern tenant loads — 200 amp service minimum for most 2–4 unit configurations. Older buildings running on 100 amp panels can't support tenants who use induction cooking, EV chargers, or multiple high-draw appliances.
4. Plumbing material throughout. Cast iron drain lines past 50 years fail catastrophically — usually mid-stack, usually at night. Polybutylene supply lines (gray, common 1978–1995) are a known insurance exclusion. Galvanized steel restricts flow and discolors water, generating tenant complaints from day one.
5. Rent roll verification against actual deposits. Don't trust the seller's spreadsheet. Demand 12 months of bank statements showing rent deposits matching the rent roll. Discrepancies of 5% or more indicate either undisclosed concession deals (free month, reduced rent for handyman services) or fabricated rents intended to inflate the sale price.
6. Lease term concentration. If all four units expire within a 60-day window, you've inherited synchronized vacancy risk. Stagger lease renewals post-close so that no more than one unit is in transition at any given time.
7. Tenant payment history per unit. Request the seller's ledger. A unit with three or more late payments in the trailing 12 months has roughly a 60% probability of eviction within 18 months. Eviction costs in most markets run $3,000–$7,000 in legal fees, lost rent, and turnover costs combined.
8. Operating expense reconciliation. Compare the seller's pro forma to actual paid invoices for taxes, insurance, utilities, repairs, and management. Sellers routinely understate expenses by 15–25% to inflate NOI. Property tax reassessment at sale alone can shift annual expenses by thousands.
9. Insurance shopability. Get a binding quote before removing contingencies. South Florida properties especially face windstorm exclusions, sinkhole carve-outs, and 4-point inspection failures that can kill financing entirely. A property that can't be insured can't be financed, and a property that can't be financed can't be sold to most buyers.
10. Zoning and legal use verification. Confirm with the municipality — in writing — that the property is legally a 4-unit, not a 3-unit with an unpermitted conversion. Unpermitted units can be ordered demolished post-close, which transforms a 4-unit income stream into a 3-unit income stream while keeping the 4-unit purchase price.
11. Capital reserves audit. Calculate what a sensible reserve fund should look like ($250–$400 per unit per month) and verify the prior owner actually maintained the building or just deferred everything. A competent property manager will document reserves transparently; if you're buying remotely, our Boca Raton Property Management framework outlines the per-unit reserve standards we use as benchmarks.
12. Local rental market comparables for the next 18 months. Are 50 or more comparable units coming online within 2 miles? Future supply crushes rent growth assumptions. The seller's pro forma assumes today's rents continue to rise. New supply assumes otherwise.

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Reading the Market: What Separates a Listable Property from a Lendable One

The listing market and the lending market filter properties differently. A property can be "for sale" without being financeable, or financeable without being a real deal. When investors look at multi family homes for sale without understanding this filter, they spend weeks underwriting properties that were never going to close. Six market signals tell you which category a property falls into.

• Price per unit vs. price per square foot. Per-unit is the right metric for income property. A 4-plex at $200K per unit in a market where comps trade at $185K per unit is overpriced by 8%, regardless of square footage. Per-square-foot is useful only for renovation scoping — how much it costs to bring units to current standard.
• Days on market by unit count. 2–4 unit properties move on residential timelines (30–60 days in healthy markets). 5+ unit properties sit longer (90–180 days typical) because the buyer pool is smaller and financing diligence is heavier. A 5-unit listed for only 30 days is either underpriced or sitting in a hot submarket — both warrant a closer look, for different reasons.
• Cap rate trend direction. Cap rates rising over 12 months mean buyers are demanding more yield (paying less for the same NOI) — typically a sign of rate-driven repricing. Cap rates falling mean buyers are accepting lower yields, often a sign of late-cycle exuberance. Buying into a falling-cap market without a value-add plan is buying the top of the cycle.
• Absorption rates of new rental construction. If a submarket added 800 new rental units in 12 months and absorbed only 500, vacancy is rising structurally. Future rent growth assumptions die here. Buyers underwriting 3% annual rent growth on a property in a negative-absorption submarket are buying a story, not a deal.
• Zoning and density regulations on the parcel. A property zoned for 4 units but operated as 6 (with garage conversions or basement units) cannot be financed legally and may not be insurable. Verify with the county records office, not the seller or the listing agent.
• Demographic and employment direction of the submarket. A 2% annual population growth combined with diversified employment (no single employer above 15% of jobs) is the floor for sustainable rent growth. Submarkets dependent on a single employer or a single industry carry concentration risk that no operating excellence can fix.

Take a working example. A 4-unit property in a Sun Belt submarket lists at $850K with $68K NOI — an 8% cap rate. Comps in the same zip code trade at 7.5% caps. On paper, the property looks attractively priced. But pulling absorption data shows 400 new units delivered in the trailing 12 months within a 1-mile radius. Rent growth that supported the seller's NOI projection will compress. Re-run the cap rate using a 5% rent haircut and the deal trades closer to 7.2% — below market. The listing is mispriced upward in disguise.

Cap rate alone is incomplete. Cap rate plus rent growth direction plus supply pipeline is what tells you whether you are buying a deal or a story.

Contrast that with a 6-unit property in a smaller market listing at $1.1M with $99K NOI — a 9% cap rate — where comps trade at 8.5%. Lower headline price, smaller submarket, but absorption is positive and the largest employer is a regional hospital system (recession-resistant by structure). The 6-unit requires commercial financing and longer due diligence, but the underlying market is structurally stronger. The 8% cap deal is the worse deal. The 9% cap deal is the better one. Headline numbers reversed reality.

Investors comparing multi-family economics to other rental asset classes sometimes pull Condos for Sale in Orlando, Florida absorption data for cross-submarket comparison — different asset, same underlying question about supply pipeline and rent growth direction.

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Financing Levers That Multiply (or Vaporize) Your Returns

Most buyers obsess over purchase price and ignore loan structure. The loan structure determines whether a 7% cap deal returns 11% cash-on-cash or 4%. The five levers below explain why two buyers acquiring identical properties can produce wildly different financial outcomes.

Loan-to-value (LTV) and refinance unlock. A buyer puts $200K down on a $1M property — 80% LTV. After 18 months of stabilization and modest rent increases, the property appraises at $1.15M. A cash-out refinance at 75% LTV pulls roughly $62K of original capital back out. That capital becomes the down payment on the next property. This is the actual mechanism of portfolio growth — not appreciation, but the recycling of equity through forced value increases via operational improvement. Investors who understand this lever build five-property portfolios from $200K. Investors who don't buy one property and stop.

DSCR-based underwriting. Commercial multi-family loans (5+ units) underwrite the property's income, not the borrower's W-2. A 1.25x DSCR means NOI must cover debt service by 25%. If NOI is $100K, allowable debt service is $80K — which at current rates dictates maximum loan size. The borrower's personal income is largely irrelevant. This is liberating for self-employed investors blocked from conventional loans by inconsistent tax returns. Self-employed buyers should run DSCR scenarios before residential scenarios.

Interest rate buydowns and seller credits. Buying down the rate by 1 point on a $750K loan costs roughly $7,500 upfront and saves about $4,800 per year at typical rate spreads. Payback is under 2 years. On a 10-year hold, the buydown returns roughly 5–6x the upfront cost. Sellers often resist headline price cuts but agree to rate buydown credits at closing because the credit costs them less than an equivalent price reduction in their net proceeds — and the buyer captures the long-term cash flow benefit. Investors weighing refinance against disposition often ask whether to Sell Your Boca Raton Home and 1031 into a larger property — buydowns can preserve the original financing structure long enough to make either path viable.

Portfolio loans for 4+ properties. Once an investor owns four or more rental properties, conventional lenders cap exposure. Portfolio lenders — typically regional banks or credit unions — bundle multiple properties under one note, offering rate concessions and underwriting flexibility in exchange for the deposit relationship. The trade-off: portfolio loans typically carry recourse provisions, meaning the borrower's personal assets back the loan. For investors building above four properties, this is the path. For investors who want to stay non-recourse, this is the wall.

Depreciation and cost segregation. Residential multi-family depreciates over 27.5 years per the IRS. A $750K building (excluding land value) generates roughly $27K per year in paper losses that offset rental income for tax purposes. Cost segregation studies reclassify portions of the building — fixtures, flooring, landscaping, specialty plumbing — into 5, 7, and 15-year schedules, accelerating depreciation into the early hold years. On a $1M property, a cost segregation study can generate $80K–$150K of first-year accelerated depreciation. This is the single most underused lever in multi-family investing, mostly because buyers either don't know it exists or assume their CPA would have mentioned it. The CPA usually won't, unless asked directly.

Tie the levers together with a concrete example. A buyer with $250K to invest has two paths. Path A: buy one $1M 4-plex with 25% down and operate it conservatively. Path B: buy one $750K 4-plex with 20% down ($150K), use $50K for value-add renovations that drive rent increases, $30K for closing costs and reserves, and $20K for a cost seg study generating about $40K in first-year tax savings — and have refinance optionality in 24 months to extract capital for property number two. Same starting capital. Path A produces one stabilized property. Path B produces a foundation for a portfolio. The property choice was secondary; the structure was primary.

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The Offer and Negotiation Playbook for Multi-Family Deals

On single-family deals, buyers negotiate price. On multi-family deals, sophisticated buyers negotiate terms — and terms compound over the hold period in ways price cuts don't. A $20K price reduction is a one-time benefit. A 0.5% rate concession on a 30-year loan is a $50K+ lifetime benefit. They look similar at closing; they aren't.

Negotiation Lever	Buyer Cost If Conceded	Long-Term Buyer Value	When to Push
Price reduction	Direct dollar-for-dollar	Affects equity only	When comps clearly support
Seller financing	Lower closing cash	Lower blended rate	When seller owns free and clear
Repair credit at close	Reduces cash to close	Funds value-add immediately	After inspection findings
Extended due diligence	Time only	Full financial review	On 5+ unit deals
Rent-up guarantee	None	Shifts vacancy risk	Under-occupied properties
Inspection contingency	None	Two bites at price	Always

Price reductions are emotionally satisfying but mathematically weak. A $20K price cut on a $750K property is 2.7% of the price. Compare that to a seller carrying a $150K second-position note at 5% when market rates are 7.5%: the buyer saves roughly $3,750 per year for the life of the note, plus the seller-carried paper improves the buyer's cash flow on day one without increasing equity requirements. Over a 10-year hold, the seller-financing concession is worth roughly 2x the price cut in pure cash flow terms.

Repair credits at closing are similarly underused. A $25K repair credit at closing preserves $25K of buyer cash, which can fund unit turnovers that produce $200/month rent increases per unit — roughly $9,600 per year of additional NOI on a 4-plex. At an 8% cap rate, that adds about $120K of property value within 12 months. The buyer turned a $25K closing credit into $120K of equity through operations. Sellers agree to repair credits more readily than price cuts because credits show up as inspection-driven adjustments, not as capitulations on list price.

Extended due diligence matters because Phase 2 financial review — tax returns, utility bills, deposit reconciliation, lease-by-lease audit — takes 30 days alone in most cases. A 30-day diligence window is functionally a 14-day window for actual underwriting once you subtract the time spent waiting for documents to arrive. Always negotiate for 60+ days on 5+ unit deals. Sellers concede this because the alternative is a buyer walking after wasting 30 days.

The rent-up guarantee is the most overlooked lever. If a property is 75% occupied at close, ask the seller for a 90-day rent-up guarantee covering the gap to 90% occupancy. Sellers often agree because they were going to lease those units anyway during the listing period. The buyer absorbs zero vacancy risk during the most volatile period of ownership — the first 90 days post-close. Buyers evaluating Boca Raton Homes for Sale in the multi-family category apply this same framework before submitting offers; the structure of the ask is more important than the size.

Every dollar negotiated outside the purchase price is a dollar not seen by the appraiser, the lender, or future buyers — but felt directly by your bank account. That's the operating principle.

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Deal-Killers That Surface Between Contract and Close

Every deal that closes badly looked fine at contract. Seven specific failure modes appear only in the diligence-to-close window. Knowing them in advance is the difference between walking away clean and absorbing a $50K mistake that nobody warned you about.

• Deferred maintenance dressed as "value-add." Sellers describe properties as having "rental upside" or "renovation potential." Translate the language: current rents are below market because the units need work, and the work has been deferred for years. A unit that "needs cosmetic updates" usually needs subfloor repair, HVAC replacement, and electrical updates that weren't visible at first walkthrough. Budget 1.5–2x the seller's suggested renovation figure as the baseline planning number.
• Tenant concentration above 30%. If two of four units generate more than half of total rent (because they're larger or were renovated recently), the loss of either tenant cuts cash flow disproportionately. Lenders flag this in underwriting. Buyers should treat concentrated tenant economics as a 25% discount to the seller's NOI when running their own model — the income exists, but it's structurally fragile.
• Rent control or rent stabilization expansion. Several markets passed rent caps in 2023–2024. Properties grandfathered under prior rules can lose that status when ownership changes hands. Verify with the municipality — not the listing agent, not the seller's attorney — whether ownership transfer triggers reclassification. A property that produces market-rate rents under the prior owner can become rent-capped under the new owner on day one.
• Appraisal gap on aggressive offers. When the offer exceeds expected appraisal by 5% or more, the buyer must cover the gap in cash or renegotiate. On a $1M property, a 5% gap is $50K of unexpected capital required at closing. Protect with an appraisal contingency or an appraisal gap coverage cap clause that limits the buyer's exposure to a defined dollar amount. Buyers comparing multi-family to single-tenant alternatives sometimes pivot toward Townhomes for Sale Near Me when financing terms tighten — different asset class, but appraisal gap mechanics behave similarly.
• Insurance binding failure. South Florida, Gulf Coast, and California properties increasingly face binding failures — the carrier underwrites the building during the application process and refuses to issue a policy. Without insurance, no lender funds. Get a binding quote during inspection, not after the inspection period closes. The difference between a quoted premium and a bound premium is the difference between a deal that closes and one that collapses two weeks before closing.
• Property manager transition costs. If the seller used in-house management, transition costs include re-keying every unit, lease re-issuance under the new owner's entity, security deposit transfers, tenant notification, and the inevitable operational disruption. Budget $300–$500 per unit for transition work, plus 30–60 days of partial dysfunction while systems get rebuilt. This isn't optional, and it isn't in any seller's pro forma.
• Unpermitted improvements or conversions. A "bonus" basement unit, a converted garage, or a finished attic generating rental income may be entirely illegal. Post-close, the county can order removal of the unpermitted space, which destroys both the rent stream from that unit and the property valuation that was based on it. Pull permits from the municipality before contingency removal. If the permit history doesn't match the marketed unit count, walk or renegotiate to the legal unit count.

Every deal that closes badly looked fine at contract. The diligence window is the only place those failures show up in time.

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Your Live-Deal Evaluation Template

Take this to the next property you're evaluating. Run every number. If any block fails, the deal doesn't survive — and you save yourself months of regret and tens of thousands in capital. When you scan multi family homes for sale in your market this week, the template below is what separates real opportunities from listings that just look like opportunities.

Block 1: Cap Rate Worksheet (run before submitting offer)

Inputs needed: annual gross rent, vacancy allowance (use 7% minimum regardless of seller's claim), operating expenses (taxes, insurance, utilities, maintenance, management), and purchase price.

Calculation: NOI equals gross rent times (1 minus vacancy) minus operating expenses. Cap rate equals NOI divided by purchase price.

Test: Is your cap rate within 0.5% of submarket comps? If lower, what specific value-add justifies the premium? If you can't name the upside in one sentence, the premium isn't justified.

Block 2: Cash-on-Cash Return Projection (run before financing application)

Inputs needed: down payment, closing costs, immediate capital expenditures required, and projected annual cash flow after debt service.

Calculation: Annual cash flow divided by total cash invested.

Test: Is cash-on-cash above 7% in year one? If not, what specifically changes in year two to justify the buy? "Rents will rise" is not an answer — it's an assumption. The answer should name a specific operational change: lease turnover, sub-metering utilities, eliminating concessions.

Block 3: Financing Scenario Stress Test (run three versions)

• Conservative: current rates plus 1%, vacancy at 10%, expenses 15% higher than quoted
• Market: current rates as quoted, vacancy 7%, expenses as quoted
• Aggressive: rate buydown of 0.75%, vacancy 5%, expenses as quoted

Test: Does the conservative scenario still cover debt service at 1.10x DSCR? If not, you're overleveraged. The conservative scenario is what actually happens in years 3–7 of most hold periods. If the deal only works under the market or aggressive scenarios, it doesn't work.

Block 4: Go/No-Go Framework (binary tests)

• Does the cap rate meet or exceed submarket median? (Yes / No)
• Is the property zoned for its current use, with permits matching unit count? (Yes / No)
• Did insurance bind at a workable premium during inspection? (Yes / No)
• Is the seller's NOI within 5% of your verified reconstruction from bank statements? (Yes / No)
• Are at least 3 of 4 units on current-market leases, not legacy below-market rents? (Yes / No)

Decision rule: four or five "Yes" answers means proceed. Three or fewer means walk. The framework is binary on purpose — qualitative judgment is where deals get rationalized into closing badly.

Block 5: 6-Month Post-Close Review Schedule

• Month 1: Confirm rent collections match the underwriting model line by line
• Month 2: Reconcile actual operating expenses against your projections; flag variances over 10%
• Month 3: Identify any tenant turnover risk before lease expirations and begin preemptive renewal conversations
• Month 4: Run a refinance scenario at current rates and your updated NOI — even if you don't refinance, you should know where the math stands
• Month 6: Run a formal valuation update. Has forced equity emerged through operations? If yes, plan the cash-out refinance and the next acquisition

Run this template on the next property listed in your market this week. If it survives all five blocks, you have a deal worth pursuing. If it fails any block, you have a property — not a deal — and there is a difference that costs six figures to learn the hard way.