What Rental Property ROI Actually Measures
ROI (return on investment) expresses your net profit as a percentage of what you put in. For rental property, "what you put in" can mean your total purchase price, your out-of-pocket cash, or your equity depending on which question you are trying to answer. That is why investors use several related metrics rather than a single number.
The three metrics that matter most are: simple ROI (good for a quick sanity check), cap rate (used to compare properties independently of financing), and cash-on-cash return (used to evaluate leveraged deals). Each answers a different question, and knowing which one to use prevents costly misreads.
Simple ROI: The Quick Sanity Check
Simple ROI divides your annual net profit by your total investment and multiplies by 100. The formula is: ROI = (Annual Net Profit / Total Investment) x 100.
Example: you purchased a rental for $250,000 with $60,000 down. After mortgage, taxes, insurance, maintenance, and vacancy, your net annual profit is $4,800. Dividing $4,800 by $250,000 (total property value) gives a 1.9% ROI on the asset. Dividing by $60,000 (cash invested) gives an 8% cash return. Both numbers are correct; they answer different questions.
Simple ROI is a starting point, not a final verdict. It ignores how the deal is financed, local market comparables, and appreciation. Use it to screen opportunities quickly before running deeper numbers.
- Annual Net Profit = Gross Rent - (Mortgage + Taxes + Insurance + Maintenance + Property Management + Vacancy Reserve)
- Use total purchase price in the denominator when comparing across markets
- Use cash invested when evaluating your own leveraged return
Cap Rate: Comparing Properties Without Financing Noise
Capitalization rate strips out your mortgage so you can compare a fully financed deal with an all-cash purchase side by side. The formula is: Cap Rate = (Net Operating Income / Current Property Value) x 100. Net Operating Income (NOI) is your gross rent minus all operating expenses, but before debt service.
Using the same example: gross annual rent is $18,000, operating expenses (excluding mortgage) total $9,600, so NOI is $8,400. Dividing by the $250,000 property value gives a cap rate of 3.4%. In a market where comparable rentals trade at a 5% cap rate, this deal is priced aggressively. In a tight urban market with 3% caps, it looks fine.
Cap rate is most useful when you are comparing acquisition targets or benchmarking an existing property against local sales. Revun tracks income and expense data per door, which makes pulling the NOI figure for a cap rate calculation straightforward. You can also run the numbers directly with the Revun cap rate calculator at /tools/cap-rate-calculator/ or dig into the definition at /glossary/cap-rate/.
- Higher cap rate = higher yield, but often higher risk or a weaker market
- Lower cap rate = compressed yield, typical in high-demand urban markets
- Cap rate does not change with your loan terms, making it a clean apples-to-apples comparison
Cash-on-Cash Return: What Leverage Actually Does for You
Cash-on-cash return (CoC) measures how much cash your cash actually earns in year one. It is the most relevant number for investors using a mortgage because it reflects the real performance of the dollars you personally put into the deal. Formula: CoC Return = (Annual Pre-Tax Cash Flow / Total Cash Invested) x 100.
Annual pre-tax cash flow is NOI minus your annual debt service (principal and interest). If your mortgage payment is $12,000 per year and NOI is $8,400, your cash flow is negative ($3,600), which means this deal at current rents does not pencil with a standard loan. A strong CoC target for most markets sits between 6% and 12%. Below 6% leaves little margin for surprises; above 12% on a stabilized property is a meaningful find.
The Revun cash-on-cash return calculator at /tools/cash-on-cash-return-calculator/ lets you plug in your actual debt service, closing costs, and initial repair budget so your denominator reflects real sunk cash rather than an estimate.
- Include closing costs, inspection fees, and initial repairs in your total cash invested figure
- CoC return drops as you refinance into a higher loan balance
- Use CoC alongside cap rate: a high CoC on a low-cap-rate property usually means aggressive leverage
Tracking ROI Accurately Over Time
A one-time ROI calculation at purchase tells you whether a deal made sense on day one. Tracking it monthly tells you whether the deal is still performing. Expenses drift upward, vacancy spikes, rent rolls change, and deferred maintenance can quietly erode a strong initial return into a mediocre one.
The practical habits that keep your numbers accurate are consistent income and expense categorization, a documented vacancy rate per unit, and a realistic reserve line for capital expenditures (roofs, HVAC, appliances). A common mistake is treating a year with no capital repairs as proof the property runs lean, then being blindsided by a $12,000 HVAC replacement.
Revun is designed around this kind of ongoing tracking. It is a property management platform built for US and Canadian landlords, with flat per-door pricing that scales from a single unit (free for one or two doors) up to large portfolios. Income, expenses, maintenance costs, and lease data all live in one place, so your ROI inputs are always current rather than estimated.
Key takeaways
- Use cap rate to compare properties without financing distortion, and cash-on-cash return to evaluate how leverage affects your personal yield.
- Net Operating Income is the foundation of both cap rate and cash-on-cash calculations. Get it right by tracking every operating expense, including a capital reserve.
- ROI is not a purchase-day number. Tracking income and expenses per door over time is the only way to know if a property is still meeting your return targets.