Rental Property Calculator
Cash flow, cap rate, cash on cash, and IRR, including the costs generic calculators leave out.
Go through the four sections and press Calculate.
How it is calculated
How it is calculated
How it is calculated
How it is calculated
How it is calculated
How it is calculated
How it is calculated
All figures are before taxes and not inflation-adjusted: they exclude depreciation, income tax, depreciation recapture, and capital gains.
Income statement · Year 1
| Item | Monthly | Annual |
|---|---|---|
| Gross Income | — | — |
| − Vacancy | — | — |
| − Operating Expenses | — | — |
| = NOI net operating income | — | — |
| − Debt Service | — | — |
| = Cash Flow | — | — |
NOI excludes debt service by definition: it measures the property, not how it was financed.
- Down payment—
- Loan amount—
- Monthly payment (principal and interest)—
- Cash invested—
Cumulative cash flow and equity
Sensitivity
Each row changes one variable and leaves the rest of the scenario alone.
| Scenario | Monthly cash flow · Year 1 | IRR |
|---|
See the year-by-year detail
| Year | Effective income | Operating expenses | NOI | Debt service | Cash flow | Cumulative cash flow | Loan balance | Property value | Equity |
|---|
How to read the numbers
Cap rate
First-year net operating income divided by the purchase price. It measures the property as an asset, independent of how you financed it. That is why the denominator is the price alone: if every buyer added their own closing costs, the result would stop being comparable against the cap rates the market publishes.
One caveat on that comparison. Published cap rates usually include a property management allowance even when the owner self-manages. If you leave the management field at zero, your cap rate will come out higher than a market cap rate calculated the standard way.
Cash on cash
First-year cash flow divided by the cash you actually put in: down payment plus closing costs plus repairs. It answers what your cash is earning, not what the property is earning.
It is a single-year figure. Some calculators add up all thirty years of the column and present the total as a return. That number does not exist in investment practice.
IRR
The annualized return across the full holding period, counting every dollar in and every dollar out: the cash you put down at closing, the cash flow of each year, and the net proceeds when you sell.
It is the only figure here that accounts for time. A property that loses money for its first ten years and then sells well can still show a solid IRR, and this is where you would see it.
These figures are before taxes. Depreciation, income tax on rental income, and capital gains on the sale are not modeled.
Rent factor
Monthly rent divided by purchase price. Investors know it as the 1% rule: rent equal to 1% of the price or better.
It is a screening tool, not a verdict. It ignores taxes, insurance, HOA, and financing entirely, which in Florida is most of the picture.
Break-even ratio
Operating expenses plus debt service, divided by gross income. It tells you what share of the rent is already committed before anything reaches you.
At 80%, a fifth of the rent can disappear before you are covering costs out of pocket. Above 100%, the rent does not cover the property even at full occupancy.
What generic calculators leave out
Most rental calculators are built for the national average. Florida is not the national average, and Miami-Dade is not Florida.
Flood insurance is a separate policy from property insurance, priced by zone and elevation, and required by lenders in high-risk areas. A calculator with a single insurance field quietly assumes you do not need it.
Special assessments are the line that has surprised the most condo owners in South Florida. Once reserve funding and milestone inspection requirements took effect, buildings that had deferred maintenance for decades sent bills running into five and six figures per unit. They arrive as one-time hits, not as a rate that compounds each year, which is why they have their own field here.
Selling costs are more than commission. In Miami-Dade, documentary stamp taxes on the deed run $0.60 per $100 on single-family homes and $1.05 per $100 on everything else, and the standard FAR/BAR contract assigns them to the seller.
The math is the easy part
A calculator tells you what a set of assumptions produces. It cannot tell you whether $3,200 is realistic rent for that specific building, whether the HOA is three months away from a reserve assessment, or whether the insurance quote in the listing will survive your closing date.
Those answers do not live in the math. They live in the building, the street, and the last four transactions on it.
And yes, we would like to work with you. Before any of that, the call is thirty minutes on the phone, about a specific property or about the market in general. Free, no credit check, nothing to prepare.
Whenever you want a second read on the numbers you just ran, that is what it is for.
This calculator is an educational tool. High Living Miami is a licensed Florida real estate brokerage, not a registered investment adviser, tax adviser, or lender. The figures produced here are estimates based on the assumptions you enter and do not constitute investment, tax, or legal advice. Actual results will differ. Consult a licensed professional before making a purchase decision.