Rental Property Calculator

Enter Calculation

Purchase

Property Purchase Price ($):

Down Payment ($):

Mortgage Rate (% APR):

Loan Term (years):

Rental Income

Monthly Rent ($):

Vacancy Rate (%):

Annual Operating Expenses

Property Tax ($/yr):

Insurance ($/yr):

HOA ($/yr):

Maintenance & Repairs (% of rent):

Property Management Fee (% of rent):

Results

Monthly Cash Flow

$57.40

Cap Rate

6.66%

Cash-on-Cash Return

1.38%

Annual NOI

$16,656

Annual Cash Flow

$689

Gross Annual Rent	$26,400.00
Effective Rent (after 5.0% vacancy)	$25,080.00
Property Tax + Insurance + HOA	$3000.0 + $1200.0 + $0.0
Maintenance (8.0%)	$2,112.00
Management (8.0%)	$2,112.00
Total Operating Expenses	$8,424.00
Net Operating Income (NOI)	$16,656.00
Mortgage P&I (monthly)	$1,330.60
Mortgage P&I (annual)	$15,967.26
Annual Cash Flow	$688.74
Cap Rate (NOI / Price)	6.662%
Cash-on-Cash (CF / Down)	1.377%
Rent / Value (1% rule check)	0.880%

What This Calculator Does

Evaluate a rental property investment by computing the four key metrics real-estate investors care about: monthly cash flow, cap rate, cash-on-cash return, and net operating income (NOI). Plug in purchase price, financing terms, monthly rent, and operating expenses to see whether the deal cash-flows.

The Four Key Metrics

• Net Operating Income (NOI): Effective annual rent (rent \(\times\) (1 − vacancy)) minus all operating expenses (taxes, insurance, HOA, maintenance, management). Excludes mortgage payments — NOI is the property's intrinsic income before financing.
• Cap Rate: NOI \(\div\) purchase price \(\times\) 100. Compares the property's earning yield independent of leverage. Use it to compare across properties.
• Cash Flow: NOI minus annual mortgage payments (principal + interest). The actual cash that lands in your pocket each year.
• Cash-on-Cash Return: annual cash flow \(\div\) down payment \(\times\) 100. Measures the return on your actual cash invested. Higher than cap rate when leverage works in your favor.

$$\text{NOI} = R_m \cdot 12 \cdot (1 - v) - \text{OpEx}$$ $$\text{Cap Rate} = \frac{\text{NOI}}{P}$$ $$\text{CoC} = \frac{\text{Annual Cash Flow}}{D}$$

How the four key metrics — NOI, cash flow, cap rate, and cash-on-cash return — are derived.

Worked Example

$250,000 property, $50,000 down, 7% / 30-year mortgage. Rents for $2,200/month, 5% vacancy, $3,000 taxes, $1,200 insurance, no HOA, 8% maintenance, 8% management:

• Annual gross rent = \(\$2{,}200 \times 12 = \$26{,}400\)
• Effective rent (5% vacancy) = \(\$26{,}400 \times 0.95 = \$25{,}080\)
• Op-ex: taxes $3,000 + insurance $1,200 + maintenance (\(\$26{,}400 \times 0.08 = \$2{,}112\)) + management (\(\$26{,}400 \times 0.08 = \$2{,}112\)) = $8,424
• NOI = \(\$25{,}080 - \$8{,}424 = \$16{,}656\)
• Cap rate = \(\$16{,}656 / \$250{,}000 =\) 6.66%
• Annual mortgage P&I (PMT formula on $200k @ 7% / 30y) \(\approx \$15{,}973\)
• Annual cash flow = \(\$16{,}656 - \$15{,}973 =\) $683
• Cash-on-cash return = \(\$683 / \$50{,}000 =\) 1.37%

This deal barely cash-flows — typical for a high-interest-rate environment. A safer target is 8–12% cash-on-cash for a leveraged buy-and-hold.

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The 1% Rule and 50% Rule

• 1% rule: monthly rent should be at least 1% of purchase price. A $250K property should rent for $2,500+. Hard to meet in 2024+ markets.
• 50% rule: operating expenses (excluding mortgage) tend to run ~50% of gross rent over the long term. If a property's listed expenses look much lower, you're probably underestimating maintenance and capex.

Both are quick screens — not substitutes for line-by-line analysis like this calculator does.

The 1% rule compares rent to price; the 50% rule estimates operating expenses.

What the Calculator Doesn't Include

• Appreciation. Property values typically rise 3–5%/year long-term, but it's not cash flow — only realized at sale.
• Tax benefits. Mortgage interest, property tax, depreciation, and operating expenses are all deductible against rental income for U.S. landlords. Effective return is usually 1–2% higher after taxes.
• Capital expenditures (CapEx). Roofs, HVAC, water heaters need replacement every 10–20 years. Add 5–10% to maintenance for a sinking fund.
• Closing costs. 2–5% of purchase price at acquisition, plus rehab if applicable. Reduces actual cash-on-cash return until paid back.