Rental Property Calculator
Found a listing and not sure if it's a good deal? Enter the numbers and get instant cash flow, cap rate, cash-on-cash return, DSCR — and a clear buy, negotiate, investigate, or pass verdict. Every assumption is editable and no signup is required.
Could work — at a lower price or better terms.
- Targets aren't met at $235,000, but they are at about $219,176 — roughly 7% below asking.
- Monthly cash flow $333 meets the $0 target.
- Cash-on-cash 6.1% is below the 8.0% target.
- Cap rate 8.3%.
Quick rules of thumb
Monthly income
Monthly expenses
5-year outlook
Estimates for education only, not investment, tax, or legal advice. Figures use your inputs and the assumptions shown — edit any of them to see the effect.
How the analysis works
Every number here comes from deterministic formulas, not a guess — the same inputs always produce the same result. We start from your rent and subtract a vacancy allowance to get effective income, subtract operating expenses to get net operating income (NOI), then subtract the mortgage and a capital-expenditure reserve to arrive at cash flow.
The verdict compares those results against your targets and stress-tests them with a conservative case. It's a rule you can inspect, not a black box — which is exactly what you want when real money is on the line.
What each number means
Cash flow
NOI − mortgage − CapEx reserveWhat lands in your pocket each month after every bill and a reserve for big-ticket repairs.
Cap rate
annual NOI ÷ purchase priceThe unleveraged yield of the property itself — useful for comparing deals regardless of financing.
Cash-on-cash return
annual cash flow ÷ cash investedYour actual return on the money you put in: down payment, closing costs, and upfront repairs.
DSCR
annual NOI ÷ annual debt serviceHow comfortably rent covers the mortgage. Lenders look for 1.2+; below 1.0 the property can't pay its own loan.
NOI
effective income − operating expensesIncome after vacancy and operating costs, before the mortgage. The foundation of most return metrics.
Max offer price
highest price that still hits your targetsWork backwards from the return you want to the most you should pay — the number to bring to a negotiation.
A worked example
The calculator loads with a sample $235,000 single-family rental at $2,400/month, 25% down at 7% over 30 years. After a full 5% vacancy allowance and 10% set aside for maintenance and CapEx, it produces about an 8% cap rate and roughly $330/month of cash flow — enough to be interesting, but short of an 8% cash-on-cash target. So the verdict lands on Negotiate, with a maximum offer around $219,000: the price at which the deal would hit those targets, and the figure worth taking into a negotiation. Change the price or rent and everything updates immediately.
Which expenses to include
The fastest way to overpay for a rental is to leave costs out of the analysis. "Rent minus the mortgage" ignores the four or five expenses that quietly decide whether a property makes money. Here's what belongs in an honest pro forma, and why.
Property taxes
Often the largest operating cost after the mortgage, and they can jump after a sale reassesses the property. Use the county's figure, not the seller's old bill.
Insurance
Landlord (not homeowner) policies cost more, and premiums have risen sharply in storm-, flood-, and wildfire-prone areas. Get a real quote before you commit.
Vacancy
No rental stays occupied 100% of the time. A 5–8% allowance covers turnover, listing time, and the occasional bad month — leaving it out inflates every return.
Maintenance & repairs
Ongoing fixes: plumbing, appliances, paint, landscaping. A common starting point is 5–10% of rent, higher for older properties.
Capital expenditures (CapEx)
The big-ticket replacements — roof, HVAC, water heater, flooring. They're rare but expensive, so you reserve a little every month rather than getting blindsided.
Property management
8–12% of collected rent if you hire out, and worth budgeting even if you self-manage, so the numbers hold up if your life changes.
HOA & owner-paid utilities
Condo or HOA dues, plus any water, sewer, trash, or common-area utilities the owner covers rather than the tenant.
Reserves & the unexpected
Licensing, legal, accounting, pest control, snow removal — small line items that add up. Build in a cushion for what you can't foresee.
The 1%, 50%, and 70% rules
Experienced investors use quick rules of thumb to screen deals in seconds before running full numbers. They're rough — never a substitute for the real analysis above — but they tell you whether a property is worth a closer look. The calculator shows all three.
The 1% rule
Monthly rent should be at least 1% of the purchase price — a $200,000 property should rent for roughly $2,000. Properties that clear 1% often cash flow; those well below it usually rely on appreciation. It's gotten harder to hit in expensive markets, so treat it as a filter, not a verdict.
The 50% rule
Assume operating expenses (everything except the mortgage) will run about half of gross rent over the long term. Subtract the mortgage from the other half and you have a fast cash-flow estimate. It's a sanity check against optimistic expense numbers — if your detailed budget is far under 50%, double-check it.
The 70% rule
Mainly for flips and BRRRR deals: don't pay more than 70% of the after-repair value minus repair costs. It builds in a margin for holding and selling costs plus profit. Our maximum offer calculator computes it alongside a buy-and-hold ceiling.
How to read your verdict
The verdict turns a wall of numbers into a decision. It compares your results against your targets, then stress-tests them with a conservative case — lower rent, higher vacancy and upkeep, no appreciation — so a deal that only works in a perfect world doesn't earn a pass.
Promising
Meets your targets and still holds up under the conservative case. A solid candidate — verify the inputs and move.
Negotiate
Doesn't quite work at the asking price, but would at a lower one. The calculator shows the maximum price that does — your negotiating anchor.
Investigate
Borderline, or the margin is thin under stress. Worth a closer look at rent comps, real expenses, and condition before deciding.
High Risk
Fails key targets or can't cover its own mortgage. Usually a pass unless the price drops substantially or the rent picture changes.
Confidence is separate from the verdict: a great-looking deal built on estimated taxes, insurance, and rent is Promising with low confidence, not a sure thing. Replace the flagged estimates with real numbers to raise it.
Frequently asked questions
What is a good cash-on-cash return on a rental property?
Many buy-and-hold investors look for 8% or more, though it depends on the market, risk, and your goals. A lower cash-on-cash return can still make sense when appreciation, loan paydown, and tax benefits are strong. This calculator lets you set your own target and shows whether a property meets it.
Does the calculator include vacancy and maintenance?
Yes. It applies a vacancy allowance and reserves for maintenance and capital expenditures (roofs, HVAC, appliances), because ignoring them is the most common way beginners overestimate cash flow. Every assumption is editable and shown, so you can match your local reality.
How is the buy/pass verdict decided?
The verdict is rule-based, not a black box. It compares the property's cash flow, cash-on-cash return, and DSCR against your targets, then stress-tests them with a conservative case (lower rent, higher vacancy and upkeep, no appreciation). The same inputs always produce the same verdict.
Do I need to create an account?
No. The full calculation, including the verdict and the maximum offer price, is free and requires no signup. You can analyze as many properties as you like.
How much should I put down on a rental property?
Investment properties usually require more down than a primary home — commonly 20–25% for a conventional loan, sometimes more for multi-unit properties. A larger down payment lowers your monthly payment and improves cash flow and DSCR, but ties up more cash and reduces your cash-on-cash return. Try 20% and 25% in the calculator to see the trade-off for your specific deal.
How do I estimate what a property will rent for?
Look at what comparable units nearby are actually listed and leased for — same bedroom and bathroom count, similar size, condition, and location. Rent estimate tools and recent listings give a range; be conservative and use the lower end. Rent is the single most important input, so a small overestimate can turn a good-looking deal into a losing one.
Should I self-manage or hire a property manager?
Professional management typically costs 8–12% of collected rent and is worth budgeting for even if you plan to self-manage at first — it protects you if your situation changes and keeps the analysis honest. Set management to 0% only if you're certain you'll manage the property yourself for the whole hold, and understand that's real work, not free.
Can I analyze a duplex, triplex, or fourplex?
Yes. Enter the total combined rent from all units as the monthly rent and the total expenses for the building. Small multi-unit properties (2–4 units) are analyzed with the same cash flow, cap rate, and return math as a single-family rental — they simply spread vacancy risk across more units.
Is this financial advice?
No. RentalRundown gives educational estimates to help you think through a decision. Property taxes, insurance, rents, and regulations vary widely — verify every figure and consult licensed professionals before making an offer.