Rental Assessment Calculator
Most rental listings die in five minutes of arithmetic. The 1% rule, the 50% rule, cap rate, cash-on-cash return, and DSCR each catch a different kind of bad deal, and a property has to survive all five before it deserves a full analysis. This rental assessment calculator runs the five screens at once and gives you a pass/fail verdict: a fast filter, not a final decision.
Quick Answer
A $220,000 property renting for $2,400/month, bought with $44,000 down plus $10,600 in closing and repairs ($176,000 at 7% for 30 years, $1,170.93/month), nets $1,528/month NOI after $872 of expenses. That is an 8.33% cap rate, $357/month cash flow, 7.85% cash-on-cash on $54,600 invested, and a 1.30 DSCR: 5/5 screens pass.
- Five screens, one verdict. The 1% rule, 50% rule, cap rate, cash-on-cash, and DSCR each catch different bad deals. A property must survive all five to earn a full analysis.
- Vacancy and management are not optional. This example budgets 5% vacancy and 8% management ($312/month combined). Deals that skip them look profitable until the first empty month.
- DSCR is the lender’s screen. Most investment-property lenders want DSCR of 1.2 or better: the property’s income must cover the mortgage with room to spare.
- Screening is not analysis. These five numbers say nothing about appreciation, taxes, big capital expenses, or the neighborhood. Pass the screens, then do the real work.
The five screens, and what each one catches
Cap rate and DSCR both start from net operating income: the rent left after operating expenses, before the mortgage. Here is how the worked example scores:
| Screen | Rule | This deal | What it catches |
|---|---|---|---|
| 1% rule | Monthly rent ≥ 1% of price | 1.09% PASS | Overpriced markets where rent can’t support the price |
| 50% rule | Expenses ≤ 50% of rent | 36.3% PASS | Expense-heavy properties (taxes, HOA, old buildings) |
| Cap rate | NOI / price ≥ 7% | 8.33% PASS | Low-yield properties regardless of financing |
| Cash-on-cash | Cash flow / cash invested ≥ 7% | 7.85% PASS | Deals where leverage doesn’t earn its keep |
| DSCR | NOI / debt service ≥ 1.20 | 1.30 PASS | Properties that can’t comfortably carry their mortgage |
Screening is not analysis
These five screens deliberately ignore the slow variables: appreciation, tax benefits like depreciation, capital expenditures (a $12,000 roof is not “maintenance”), rent growth, and neighborhood trajectory. They also ignore your financing reality: the 7% rate here is a placeholder, so check current investment-property rates before trusting the DSCR, and note that lenders must disclose loan terms under federal rules. Think of this tool as the bouncer, not the judge. If a deal passes all five, run it through our buying rental property calculator for the full deal analysis: multi-year projections, tax effects, and sensitivity to vacancy and rate changes. For the financing side, the early loan payoff calculator shows what extra payments do to an investment loan, and the home equity credit line calculator sizes payments if you fund the down payment from a HELOC. For the purchase process itself, the CFPB’s Owning a Home toolkit walks through offers, inspections, and closing.
What other rental assessment calculators get wrong
Most rental calculators report one metric, usually cap rate or cash flow, and call it analysis. Three things go missing. First, vacancy and management: tools that let you enter $0 for both produce fantasy cash flow, so this calculator defaults vacancy to 5% and prompts for management. Second, cash invested: many divide by the down payment alone and ignore closing costs and immediate repairs, inflating cash-on-cash. This calculator counts every dollar you actually put in ($54,600 here, not $44,000). Third, DSCR: almost no screening tool includes the lender’s own metric, even though a DSCR under 1.2 can kill your financing.
Reading the verdict: what 5/5, 3/5 and 2/5 mean
The verdict counts screens, not quality. A 5/5 result means every bar cleared, a 3/5 or 4/5 result means the deal deserves a closer look, and a 2/5 or lower result means the deal is weak on paper.
That count maps directly to the badge the calculator shows. Five passes give a strong-deal badge and a prompt to run a full analysis. Three or four passes give a deeper-look badge with the count stated plainly. Two or fewer passes give a weak-deal badge. The count alone is not the whole story: a deal that fails only the DSCR screen still carries a financing risk, because a lender can decline a deal that cash flows, while a deal that fails only the 50% rule may simply have unusually high taxes or HOA dues worth verifying against the actual bills.
A 5/5 result is still not an offer. Screening uses today’s numbers and five bars, and it says nothing about the roof, the tenant, the street, or the tax return. Treat a pass as permission to spend time on the deal: verify the rent against comparable listings, confirm the tax and insurance figures against real bills, and then run the full analysis before writing anything down.
The verdict is most useful when the inputs stay honest across listings. Run every property with the same vacancy assumption, the same management allowance, and rent taken from comparable listings rather than from the seller’s brochure, or the count stops comparing like with like. A property that only passes because its rent was copied from an optimistic listing will fail the same screens the moment a tenant actually signs, so re-run any 5/5 deal once more with the lower end of the comparable rent range. If it still passes, the verdict is worth something. If it drops to 3/5, the deal was never a 5/5 deal at all, only a 5/5 listing.
Which input moves the verdict first
Rent and rate move this verdict more than any expense line, because they feed several screens at once. The table below holds every other input at the worked example and changes one thing at a time, using the calculator’s own outputs.
| Scenario | Cash flow | Cap rate | Cash-on-cash | DSCR | Screens |
|---|---|---|---|---|---|
| Worked example: $2,400 rent, 7% rate | $357/mo | 8.33% | 7.85% | 1.30 | 5/5 |
| Rent cut to $2,200, all else the same | $183/mo | 7.39% | 4.02% | 1.16 | 3/5 |
| Rate raised to 8%, all else the same | $237/mo | 8.33% | 5.20% | 1.18 | 3/5 |
The rent cut fails two screens at once: cash-on-cash falls to 4.02% and DSCR falls to 1.16, while the 1% rule, the 50% rule and cap rate still pass. The rate rise fails the same two screens but leaves cap rate untouched at 8.33%, which is exactly what cap rate is for: it grades the property, not the loan. Before raising the rent in the calculator to make a deal pass, check what rent the market actually supports with our possible rent calculator. One more limitation to carry with you: vacancy is fixed at 5% of rent in this tool, so if your market runs emptier than that, treat any verdict as optimistic and test the deal again with higher expense inputs.
Frequently Asked Questions
Monthly rent should be at least 1% of the purchase price: a $220,000 property should rent for $2,200 or more. It is a rough screening heuristic, not a valuation method, and it fails in expensive coastal markets.
Cap rate = annual net operating income / purchase price. It measures the property’s yield independent of financing. This tool uses 7% as the screening bar; 8.33% here passes comfortably.
Annual pre-tax cash flow divided by total cash invested (down payment + closing + repairs). Unlike cap rate, it reflects your leverage: 7.85% here means each invested dollar earns 7.85 cents a year.
The debt service coverage ratio = NOI / annual mortgage payments. It shows how comfortably the property covers its loan; lenders typically want 1.2 or higher. At 1.30, this deal clears the bar.
A screening shortcut that assumes operating expenses (not counting the mortgage) will run about 50% of gross rent. If a deal still cash-flows under that assumption, it deserves a closer look. This property runs 36.3%, well under.
Yes: mortgage interest, property tax, insurance, maintenance, management fees, and depreciation are generally deductible against rental income. Keep records from day one.
Screening uses today’s numbers and five pass/fail bars; a full analysis projects years of rent growth, expenses, taxes, and sale proceeds. Use this tool to filter 50 listings down to 5, then analyze those 5 deeply.
Add This Calculator to Your Website
References
- Steadily. How to Calculate Cap Rates for Rental Real Estate. Accessed October 25, 2026.
- Propelx. Cap Rate, Cash-on-Cash Return and IRR in U.S. Real Estate Investing. Accessed October 25, 2026.
- Internal Revenue Service. Publication 527, Residential Rental Property (deductible expenses and depreciation). Accessed October 25, 2026.
- Consumer Financial Protection Bureau. Owning a Home (homebuying and mortgage guidance). Accessed October 25, 2026.
- Consumer Financial Protection Bureau. Regulation Z, 12 CFR Part 1026 (mortgage disclosure rules). Accessed October 25, 2026.
- Freddie Mac. Primary Mortgage Market Survey (current mortgage rate data). Accessed October 25, 2026.
- RefiGuide. How to Calculate DSCR: The Formula Lenders Actually Use. Accessed October 25, 2026.
- Internal Revenue Service. Tips on Rental Real Estate Income, Deductions, and Recordkeeping. Accessed October 25, 2026.
- U.S. Census Bureau. American Housing Survey (rental housing data). Accessed October 25, 2026.
- Corporate Finance Institute. Debt Service Coverage Ratio (DSCR formula and lender thresholds). Accessed October 25, 2026.