How to analyze a rental property: the complete walkthrough (with real numbers)
Income, expenses, financing, returns — the full underwriting sequence, the 1% rule and the 50% rule put in their place, and the numbers that make a lender say yes.
How do you analyze a rental property? Four steps: establish honest income, subtract honest expenses (the full list, not the mortgage-and-taxes version), apply your financing, and judge the resulting three numbers — cashflow per door, cash-on-cash return, and DSCR — against your floor. The whole analysis fits on one page and takes fifteen minutes. Screening rules like the 1% rule can tell you which properties deserve those fifteen minutes; they cannot tell you to buy.
Step 1 — Income you can defend
Use the rent the market pays, not the rent the listing hopes for: three comparable rentals, same beds/baths/condition, within a mile. Then discount for vacancy — 5-8% (one turnover every 18-24 months) is honest for most markets. A seller's "projected rents after light updates" is not income; it is a renovation project wearing an income statement.
Step 2 — The expenses that actually occur
The classic beginner analysis counts mortgage, taxes, insurance — and calls the rest profit. Here's where the rent on a real $1,800/month single-family rental actually goes over a full ownership cycle:
Two lines deserve defense because every optimistic analysis deletes them: CapEx is real spending on a delay timer, and management belongs in the math even if you self-manage — otherwise you bought a part-time job and called its wages "returns."
The 50% rule summarizes all of this: across long holds, operating expenses (everything above the mortgage line) run near half of gross rent. Any analysis showing 25% expenses is missing lines, not finding alpha.
Step 3 — Screening rules, used correctly
| 1% rule | 50% rule | |
|---|---|---|
| Says | Monthly rent ≥ 1% of purchase price | Operating expenses ≈ 50% of rent (before mortgage) |
| Job | 10-second screen: is this worth analyzing? | 10-second expense sanity check |
| Today's reality | Rare in strong metros; 0.7-0.8% is the working band — which is why full analysis matters more, not less | Still roughly right for long holds; newer property trends lower, older higher |
| Never | A buy signal — a 1.2% property can still lose money | A substitute for line-item expenses on a deal you'll offer on |
Step 4 — The three verdict numbers
After financing, the analysis compresses to three numbers — the same three the deal analyzer computes:
- 01Cashflow per door — the survival numberNOI minus debt service, monthly. Floor: $100-200/door minimum at honest numbers. Its job is margin, not income — thin-but-positive at conservative inputs is acceptable; negative is a different strategy.
- 02Cash-on-cash return — the efficiency numberAnnual cashflow ÷ total cash invested (down payment + closing + immediate repairs). 5-8% is the typical band for conservatively financed deals at today's rates; remember this counts only one of the five profit centers.
- 03DSCR — the lender's numberNOI ÷ annual debt service. Below 1.20 most lenders stop reading; 1.25+ is comfortable; 1.30 at 90% occupancy is the standard this site uses for 'hold-safe.' If DSCR fails, no other number matters.
The fifteen-minute discipline
The point of a repeatable analysis isn't precision — it's volume. Underwrite ten properties a week with the same honest template and two things happen: your market's real numbers internalize (you'll price a listing from the thumbnail), and the occasional genuine deal becomes obvious the moment it appears, because it looks nothing like the other nine. That reps-before-buying habit is Foundation-stage work — the analysis skill compounds before the capital does.
Frequently asked questions
+How do you analyze a rental property?
Four steps: (1) establish market rent from comparables and discount for 5-8% vacancy; (2) subtract full operating expenses — taxes, insurance, maintenance, CapEx reserves, management — which average ~50% of rent; (3) subtract the mortgage payment; (4) judge the result on cashflow per door (≥$100-200), cash-on-cash return (≥5-8%), and DSCR (≥1.2-1.25).
+What is the 1% rule in real estate?
A screening shortcut: a property whose monthly rent is at least 1% of its purchase price ($2,000 rent on $200,000) is likely to cashflow and worth full analysis. In today's strong markets most viable deals screen at 0.7-0.9% — the rule filters what to analyze; it is never a reason to buy.
+What is the 50% rule for rental properties?
Over a full ownership cycle, operating expenses — vacancy, taxes, insurance, maintenance, capital expenditures, management, but NOT the mortgage — tend to consume about half of gross rent. Analyses showing dramatically lower expense ratios are usually missing CapEx, vacancy, or management lines.
+What is a good cash-on-cash return on a rental?
At today's rates, 5-8% is a solid band for a conservatively financed long-term hold, and 8%+ is strong. Cash-on-cash counts only cashflow — appreciation, loan paydown and tax benefits typically push well-bought total returns to 15%+ on invested cash.
+What DSCR do lenders require for rental loans?
Most DSCR lenders want 1.20-1.25 minimum — the property's net operating income must exceed the annual debt payment by 20-25%. Stronger ratios earn better rates. A property that can't clear 1.2 at honest rents is telling you the price or the financing is wrong.
+Should I include property management costs if I self-manage?
Yes — always underwrite 8-10% for management. If the deal only works when your labor is free, it doesn't work; and pricing management in from day one means scaling (or burnout) never breaks the portfolio's math.