Rental Property Calculator

Introduction

This Rental Property Calculator builds an investor-style pro forma from purchase price, financing, gross rent, vacancy, and operating expenses. It reports net operating income, monthly cash flow after debt service, cap rate, and cash-on-cash return so you can compare rentals on economics rather than curb appeal alone.

Who this calculator is for

Residential buy-and-hold investors use this page before they write an offer or during due diligence after inspection. The numbers discipline enthusiasm: a property that looks perfect may fail a five percent cash-on-cash hurdle once vacancy and maintenance are honest. Lenders reviewing DSCR on non-owner loans may also want NOI and debt service spelled out clearly.

Owner-occupants estimating house-hack cash flow can use it too. For a broader property hub without line-item focus, see the Real Estate Calculator. Primary residence PITI alone belongs in the Mortgage Calculator.

What it estimates

Gross rent minus vacancy yields effective gross income. Subtract operating expenses (tax, insurance, maintenance, management, HOA, utilities if landlord-paid) to get net operating income. Subtract annual debt service from NOI for pre-tax cash flow. Cap rate is NOI divided by purchase price; cash-on-cash is annual cash flow divided by total cash invested including down payment and closing costs.

Depreciation, passive loss limits, 1031 exchanges, and state income tax on rent are not calculated. Capital expenditures such as roof replacement are often smoothed into a maintenance line rather than modeled as lumpy events.

Inputs explained

Use market rent for a new acquisition unless a lease is assigned at closing.

• Purchase price: Contract price before credits; use separate fields for closing costs in cash invested.
• Down payment and loan terms: Investor loans often require twenty to twenty-five percent down; enter actual quote.
• Monthly gross rent: Expected rent at lease-up or in-place rent on renewal.
• Vacancy rate: Percent of gross rent lost to turnover and non-payment, often five to ten percent in stable markets.
• Monthly or annual expenses: Property tax, insurance, repairs, capex reserve, management fee, HOA, lawn, snow, utilities.
• Closing costs (optional): Added to numerator and denominator of cash-on-cash.

How to read the results

Cap rate answers unlevered yield: would you buy this property for cash at this NOI? Cash-on-cash answers levered yield on your out-of-pocket dollars. A deal can show a six cap with negative cash-on-cash if the loan payment exceeds NOI, which is common in appreciation markets and risky if rents stall.

Compare to your cost of capital and to alternative investments. Stress vacancy two points higher and rent five percent lower; if cash flow turns deeply negative, negotiate price or walk. Verify debt payment with the Amortization Calculator if the PI line looks off.

Worked example

Price $350,000 with twenty-five percent down and financing on $262,500 at 7.00% thirty-year: debt service about $21,000 per year. Gross rent $2,650 monthly is $31,800 annually. Eight percent vacancy removes $2,544, effective gross $29,256. Expenses $900 monthly ($10,800 yearly) leave NOI near $18,456. Cap rate about 5.3 percent.

NOI $18,456 minus debt $21,000 gives negative cash flow near $2,544 per year before tax effects. Cash-on-cash on $87,500 down plus closing might be slightly negative. The investor is betting on appreciation, rent growth, or a future refi, not current yield.

Practical use cases

Set minimum cash-on-cash and cap filters for your market. Compare a turnkey with eight percent management fee against self-manage with higher maintenance reserve. Model an ADU rent line on a house hack.

Before raising rents, rerun with proposed rent to see DSCR headroom for a future refi in the Refinance Calculator. Compare against stock market return assumptions outside this tool.

Limitations and related tools

Short-term rental rules, rent control, tenant quality, and eviction timelines are not quantified. Commercial triple-net and multi-family utility splits differ from this residential template. Insurance spikes after claims and tax reassessments after purchase can lag your inputs.

For affordability of an owner-occupied purchase use the House Affordability Calculator. For cash to close use the Down Payment Calculator. New investors should read mortgage basics when mixing primary residence and rental financing.

How It Works

1. Enter price and financing. Type purchase price, down payment, rate, and term to establish debt service.
2. Set rent and vacancy. Enter gross monthly rent and a realistic vacancy percentage for your submarket.
3. Fill expense lines. Include tax, insurance, maintenance, management, HOA, and landlord-paid utilities.
4. Review cap rate and cash flow. Calculate and compare cap rate, NOI, monthly cash flow, and cash-on-cash to your hurdles.

Formula and methodology

The Rental Property Calculator uses this identity for the scenario you enter. A bank, payroll system, or tax program may round on a 360-day year or average daily balance, so a statement can differ by a small amount.