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Cash flow calculator
What actually lands in your account each month after the mortgage, the expenses, and the weeks the unit sits empty, with reserves counted, not wished away.
The property runs $436 short every month: $5,238 a year out of pocket, before any surprise repair.
How rental cash flow works
Cash flow is the simplest metric in real estate and the most frequently overstated, because three of its subtractions are invisible on any given month. Rent minus mortgage looks like $700. Rent minus mortgage minus the roof you'll replace in year nine, the two months the unit sat empty, and the water heater that failed in February looks like $150.
The three lines that get skipped
Vacancy, maintenance, and capital reserves cost nothing in a good month and everything in a bad one. Budgeting each at roughly 5 percent of rent spreads their real long-run cost evenly instead of letting a single turnover erase a year of profit. A property that only cash-flows when those lines are set to zero doesn't cash-flow.
Per door
Investors compare deals in dollars per unit per month because it normalizes across property sizes. A duplex at $180 per door beats a fourplex at $90, even though the fourplex produces more total dollars: it's doing it with twice the units and twice the operational surface area.
Cash flow questions
What is good cash flow per door?
A common target is $100 to $200 per unit per month after every expense and reserve. But the figure matters less than the honesty behind it. A $300 per door number computed without vacancy or capital reserves is worth less than a $100 one that includes both.
Is negative cash flow always a dealbreaker?
Not automatically, but it changes what you're buying. A negative-cash-flow property costs you money monthly, so the return has to arrive through appreciation and loan paydown instead: a bet on the market rather than on the building. If you take it, hold reserves deep enough to fund the shortfall through a long vacancy.
Should cash flow include principal paydown?
No. Cash flow is money in your pocket, and the principal portion of your payment leaves your account even though it builds equity. Count paydown as a separate source of return alongside cash flow and appreciation; the rental ROI calculator adds all three together.
Every calculator
Cash flow on a real listing, in seconds.
Paste an address and Faro fills rent, taxes, and insurance from real data, then shows the cash flow at every price on the ladder.
Estimates for analysis and educational use only: not financial, investment, tax, or legal advice. Verify every number independently before making a purchase decision.