Rental Property Calculator

Analyze cash flow, break-even rent, cap rate, and long-term returns before you invest

Monthly Cash Flow
-$517
-$6,204/year
Break-Even Rent
$3,044
$544 below break-even
Cap Rate
4.6%
NOI / property value
Cash-on-Cash
-7.7%
annual return on cash
Property & Financing
$350K
20% ($70K)
%
3% ($11K)
%
7%
%
30 yrs
yrs
Rental Income
$2,500
$0
5%
%
Annual Expenses
$4,200
$150
1% ($4K/yr)
%
10% of rent
%
$0
3%
%
Investment Decision Checks
Negative Cash Flow
-$517/mo · -$6,204/yr after all expenses
1% Rule: 0.71% of price
Rent is below 1% of price ($3,500/mo target)
Cap Rate: 4.6%
Below 6% — lower return relative to property value
Cash-on-Cash: -7.7%
Below 8% — consider if this beats alternative investments
Monthly Income vs Expenses
Mortgage (P+I)$1,863
Property Tax$350/mo
Insurance$150/mo
Maintenance$292/mo
Management$238/mo
Total monthly expenses$2,892
10-Year Wealth Accumulation
Total Wealth
Equity (Down Pmt + Paydown)
Appreciation
Cumulative Cash Flow
$168K
Year 10 Wealth
$230K
Year 10 Equity
$120K
Appreciation (10 yr)
$-62K
10-yr Cash Flow
Rent Sensitivity Analysis

How monthly cash flow changes with rent ±$500

Full Investment Metrics
Loan Amount$280,000
Total Cash Invested$80,500
Monthly Mortgage (P+I)$1,863
Break-Even Rent$3,044
Effective Monthly Rent$2,375
Net Operating Income$16,150/yr
Gross Rental Yield8.6%
Net Rental Yield4.6%
Cap Rate4.6%
Cash-on-Cash Return-7.7%
Gross Rent Multiplier11.7x
1% Rule (rent / price)0.71%

How the Rental Property Calculator works

This calculator evaluates a rental property the way investors do: it computes the break-even rent, cap rate, cash-on-cash return, and projects total wealth built over a decade from cash flow, loan paydown, and appreciation combined.

Good rental analysis is mostly about honest expenses. Mortgage, taxes, and insurance are obvious; vacancy, maintenance, capital expenditures (roofs, HVAC), and property management are the line items that turn paper profits into real losses when ignored.

The formula
Cap rate = NOI ÷ Price · Cash-on-cash = Annual cash flow ÷ Cash invested
  • NOI — net operating income (rent − operating expenses, excluding mortgage)
  • Cash flow — NOI − debt service
  • Cash invested — down payment + closing costs + initial repairs

Tips to get the most out of it

  • Budget vacancy (5–8%), maintenance (~1% of value/year), and capex reserves even if the property is currently perfect.
  • Leverage amplifies both directions: a mortgage can turn a 6% property return into a 12% equity return — or a small dip into a negative one.
  • Run the numbers with property management (8–10% of rent) even if you'll self-manage; your time isn't free.

Frequently asked questions

What is a good cap rate?

It varies by market and risk: 4–6% is typical for desirable low-risk areas, 8%+ usually signals higher risk or management burden. Compare cap rates within the same market and property class — a "good" number in one city is unremarkable in another.

What is the 1% rule?

A screening heuristic: monthly rent of at least 1% of the purchase price suggests the property might cash flow. In many markets today it's hard to hit — treat it as a first filter, then run full numbers like this calculator does rather than relying on the shortcut.

What expenses do new landlords forget?

Vacancy between tenants, turnover costs (paint, cleaning, listing), capital expenditures like roofs and water heaters, rising insurance premiums, and property management. A property that only works at 100% occupancy with zero repairs doesn't work.

How does a rental build wealth beyond cash flow?

Three ways at once: monthly cash flow, principal paydown (tenants retire your mortgage), and appreciation. Tax treatment — depreciation deductions and deferral tools — can add more. The 10-year projection in this calculator adds those streams together.

From the Knowledge Base

How to Analyze a Rental Property: Cap Rate, Cash Flow, and the 1% Rule

Most rental listings look profitable until you count every expense. The four metrics investors actually use, with honest numbers on a real-world example.

Read the guide