DSCR, Cash-on-Cash, and the 1% Rule for Section 8 Deals
DSCR, cash-on-cash return, and the 1% rule defined for Section 8 rentals — what each metric means, how to compute it, and worked FY2026 examples.
Every rental-analysis conversation eventually collapses into three acronyms: the 1% rule, cash-on-cash return, and DSCR. They measure different things, they disagree with each other regularly, and Section 8 deals put a distinctive twist on each. Here's what they mean, how to compute them, and how to read them on a voucher deal — with real FY2026 HUD rent figures in the examples.
The 1% rule: a screen, not a verdict
Definition: monthly gross rent should be at least 1% of the purchase price.
1% test = monthly rent ÷ purchase price
It's a five-second filter for "is this even worth analyzing?" — nothing more. It ignores taxes, condition, financing, and everything else that decides whether you make money.
The Section 8 twist: use the voucher-supported rent, not the listing rent. HUD publishes Fair Market Rent for every area — ZIP by ZIP in Small Area FMR metros — and in working-class Rust Belt ZIPs it often exceeds street rent. Example with real data: the FY2026 3-bedroom Small Area FMR for Cleveland ZIP 44109 is $1,390. On a $95,000 house that's 1.46% — comfortably past the screen. The county-wide FY2026 3BR FMR in Toledo (Lucas County) is $1,380; on an $85,000 house, 1.62%.
Coastal reality check: the same test on a $400,000 house needs $4,000/month to pass, which is why spread investors live in the Midwest.
Rules of thumb about the rule: older housing stock deserves a stricter bar (capex will eat gross rent), and passing 1% with a negative FMR-to-market spread is a trap — the screen can't see quality of income. Screen with it, never decide with it.
Cash-on-cash return: your actual yield
Definition: annual pre-tax cash flow divided by the actual cash you put in.
CoC = (NOI − annual debt service) ÷ total cash invested
Where NOI = rent − operating expenses (taxes, insurance, management, maintenance/capex reserve, vacancy), and cash invested = down payment + closing costs + upfront rehab.
Worked example (illustrative deal, real FMR): that ZIP 44109 3-bedroom at $95,000 with rent underwritten at the $1,390 FY2026 SAFMR. Say line-itemed expenses run $600/month, so NOI is $790/month. Finance 80% at ~6.7%/30yr → P&I about $490/month. Cash in: $19,000 down + $3,000 closing = $22,000.
- Annual cash flow: ($790 − $490) × 12 = $3,600
- Cash-on-cash: $3,600 ÷ $22,000 ≈ 16%
The Section 8 twist: the quality of that 16% differs from an unassisted deal. The bulk of the rent arrives as a PHA direct deposit that doesn't depend on the tenant's paycheck, and voucher tenancies tend to run long, so the vacancy line you assumed is likelier to hold. Two deals with identical CoC are not identical risks.
What counts as good: with rates around 6.5–7%, many buy-and-hold investors look for high single digits to low teens; spread markets are attractive precisely because mid-teens is achievable on paper. Be suspicious of any pro-forma above ~20% — usually an expense line is missing.
DSCR: the lender's metric (and your safety margin)
Definition: net operating income divided by annual debt service.
DSCR = NOI ÷ debt service
- DSCR 1.0 = the property exactly covers its mortgage. No margin.
- DSCR 1.25 = income exceeds debt service by 25%.
Why you care even if a lender doesn't: DSCR is your cushion against everything going slightly wrong at once. From the example above: $790 NOI ÷ $490 P&I = DSCR ≈ 1.6 — the rent could fall 35%+ before the property stopped covering its own mortgage.
Why lenders care: DSCR loans — the workhorse financing for investors who'd rather qualify on the property than on personal tax returns — typically want 1.2+ for the best terms, with pricing tiers as coverage improves. Some lenders count documented HAP payments favorably when verifying rent, since a PHA deposit history is clean and consistent, but programs vary — ask.
The Section 8 twist: high-FMR/low-price ZIPs naturally generate high DSCRs, which is exactly the profile DSCR lenders price best. The metric and the strategy are unusually compatible.
Reading the three together
| Metric | Question it answers | Good screen (context-dependent) |
|---|---|---|
| 1% rule | Worth analyzing at all? | ≥ 1%, stricter for old stock |
| Cash-on-cash | What does my cash earn? | high single digits to mid-teens |
| DSCR | How safe is the mortgage? | ≥ 1.2, happier at 1.4+ |
They fail in different directions: a deal can pass 1% and still cash-flow poorly (taxes, capex); it can show great CoC with a fragile 1.1 DSCR (thin margin, high leverage); it can boast a fat DSCR with weak CoC (too much cash in). A deal worth doing usually clears all three using honest expense lines and the correct FMR for its exact ZIP.
That last part — the correct FY2026 FMR for the address, the market-rent comparison, and all three metrics computed with real expense lines — is what a RentMargin report gives you in one step: paste an address, get the full spread report free.
Educational content, not investment advice. FMR figures are HUD's published FY2026 data; prices, rates, and expenses in the examples are illustrative estimates. Underwrite every deal with local numbers.