How it works
This calculator applies vacancy to rent, subtracts property taxes, insurance, HOA, management, maintenance, and other expenses to reach NOI, then subtracts your mortgage payment to reach cash flow.
It uses the same formulas as the 713 Deal Generator, so NOI, cash flow, and cap rate agree when the same assumptions are entered. The Deal Generator also calculates the mortgage, cash-on-cash return, DSCR, and the 713 Metrics Score.
Formula
Rent × (1 − Vacancy %)
(Effective income − Operating expenses) × 12
NOI ÷ Purchase price × 100
Effective income − Operating expenses − Mortgage
Worked example
With the hypothetical default inputs — $300,000 price, $2,400 rent, a $1,497 mortgage payment — the calculator returns:
| Monthly cash flow | -$351/mo |
|---|---|
| Effective rental income | $2,280/mo |
| Operating expenses | $1,134/mo |
| Net operating income | $13,752/yr |
| Annual cash flow | -$4,212/yr |
| Cap rate | 4.58% |
All figures in this example are hypothetical and chosen to illustrate the math. They are not current Houston market averages, quotes, or forecasts.
Frequently asked questions
Where does the mortgage payment come from?
Use the Mortgage Calculator to estimate principal and interest, then enter it here. Enter 0 for an all-cash purchase.
Does this include appreciation or tax benefits?
No. It measures pre-tax operating cash flow only.
See how every assumption interacts
The 713 Deal Generator combines financing, income, operating costs, and upfront cash into a printable report with stress tests and the 713 Metrics Score.
Run the Full 713 Deal Generator713 Metrics provides educational and informational tools based on user-provided assumptions. Results are estimates and do not constitute financial, investment, tax, legal, lending, appraisal, brokerage, insurance, or real-estate advice. Verify property-specific information independently and consult appropriate licensed professionals.