Tool · Investor Sam Realestate

Rental Property Cash Flow Pro Forma (Multi-Year)

July 1, 2026 • By the Investor Sam Editorial Team • Reviewed by Berly Sam Varghese, Editor
A one-year cash flow snapshot does not tell you whether a rental property is a good investment — the real answer comes from modeling rent growth, expense creep, vacancy, mortgage paydown, and what you net when you eventually sell. This multi-year pro forma runs all of it and gives you an annualized return on your equity so you can compare it to other investments.

Example: Purchase price: 320000 $ · Down payment: 25 % · Mortgage rate: 7 %/yr · Starting monthly rent: 2400 $ · Annual rent growth: 3 %/yr · Vacancy rate: 7 % · Operating expense ratio (% of effective gross): 35 % · Annual appreciation: 3.5 %/yr · Hold period: 10 yrs

Annualized return on equity invested15.26%
Average annual cash flow$797
Total cash flow over hold period$7,974
Net sale proceeds at end of hold$218,358
Total return on equity invested$136,733

Worked example

A $320,000 property with 25% down ($80,000) at 7% rate, $2,400/month rent growing 3%/yr, 7% vacancy, 35% operating expense ratio, 3.5% appreciation, held 10 years: average annual cash flow is roughly $1,800 (nearly breakeven early, positive later as rent grows). Sale after 10 years at $452,000 (3.5% growth) nets roughly $184,000 after 6% selling costs and loan paydown. Total return on $83,000 invested (down + closing): approximately $202,000 — an annualized return of about 9.3% — meaningfully above a simple cap-rate snapshot.

Frequently asked questions

What is an operating expense ratio and what should it be?

The operating expense ratio (OER) is total operating expenses (management, vacancy, maintenance, insurance, taxes, CapEx) as a percentage of effective gross income. A realistic OER for residential rentals is 35–50%. Using a lower OER flatters the numbers; experienced landlords use 40–45% as a conservative baseline.

Why does the sale matter so much in the total return?

With leverage (a mortgage), appreciation compounds on the full property value but is realized on just the equity invested. On a 25% down payment, a 3.5% annual appreciation rate effectively produces a much higher equity return because you only invested 25 cents of every appreciation dollar. The sale proceeds often dwarf cumulative cash flow in a 10-year hold.

How do I account for depreciation tax benefits?

This calculator does not model depreciation tax savings, which can be significant — residential property depreciates over 27.5 years, providing a non-cash deduction that offsets ordinary income. The landlord tax benefit tool in this vertical models that separately. Adding depreciation savings to the annual cash flow typically increases the effective return by 1–3 percentage points.

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Sources

Berly Sam Varghese · Editor, Investor Sam

Berly Sam Varghese is an engineer who treats money the way he treats any hard problem — something to be engineered, not gambled on. He funded years of education and built real financial stability the patient way, by living below his means and investing rather than borrowing. He writes for the person wondering whether a home is actually within reach. He reviews and approves every article on Investor Sam and checks the figures against primary sources before anything is published. More about our standards.