What's a healthy cash flow?

Most investors want at least $100–$200/unit/month after all expenses including mortgage. Below $50/unit/month is risky — small increases in expenses or vacancy can push you negative.

Why use percentages for vacancy/maintenance/management?

They scale with rent, which makes them easy to compare across properties. Common defaults: vacancy 5–8% (depends on market), maintenance 1–2% of rent, management 8–10% of collected rent.

Should I include a capital-expenditure reserve?

Yes — typically $100–$300/unit/month for big-ticket items (roof, HVAC, water heater). Add it to 'Other / mo' or increase the maintenance percentage.

Why is my cash flow negative?

Likely the mortgage is too high relative to rent. The 1% rule (rent ≥ 1% of price) is a quick check — at today's interest rates you may need 1.2–1.5% to cash-flow positively.

Real Estate Tools

Cash Flow Analyzer

Analyse the monthly and annual cash flow for a rental property. Enter rental income, mortgage P&I, taxes, insurance, HOA and the standard percentage-based reserves (vacancy, maintenance, management) to see net cash flow with a clear positive/negative indicator and a colour-coded expense breakdown chart.

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How to use

1
Enter gross monthly rent
The full rent you charge before any vacancy or expense allowances.
2
Enter fixed monthly expenses
Mortgage principal & interest, property tax, insurance, HOA and any other fixed monthly costs.
3
Set percentage-based reserves
Vacancy, maintenance and management are entered as a percentage of gross rent. Common defaults: vacancy 5–8%, maintenance 1–2%, management 8–10%.
4
Read net cash flow
The result card shows monthly and annual net cash flow, with a positive/negative indicator. The bar chart shows where the money goes.

Common use cases

Decide whether a rental will be cash-flow positive before you buy.
See which expense category is eating your returns the most.
Stress-test by raising the vacancy % to model a tougher rental market.

Limitations

This calculator produces an estimate only and is not professional real-estate, tax, accounting or investment advice. Stamp-duty brackets, tax rules and fees vary by jurisdiction and change frequently — always confirm current rates with your conveyancer, tax office or financial advisor before signing anything.
Maintenance and management are computed as a percentage of gross rent. Some property managers charge a percentage of collected rent (effective gross income) — adjust the percentage to compensate.
The model is monthly and linear. It doesn't model one-off capital expenditures (roof, HVAC) — reserve for those separately, typically $200–$400/unit/month.

Frequently asked questions

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Loading Cash Flow Analyzer…

Cash Flow Analyzer

How to use

Enter gross monthly rent

The full rent you charge before any vacancy or expense allowances.

Enter fixed monthly expenses

Mortgage principal & interest, property tax, insurance, HOA and any other fixed monthly costs.

Set percentage-based reserves

Vacancy, maintenance and management are entered as a percentage of gross rent. Common defaults: vacancy 5–8%, maintenance 1–2%, management 8–10%.

Read net cash flow

The result card shows monthly and annual net cash flow, with a positive/negative indicator. The bar chart shows where the money goes.

Limitations

This calculator produces an estimate only and is not professional real-estate, tax, accounting or investment advice. Stamp-duty brackets, tax rules and fees vary by jurisdiction and change frequently — always confirm current rates with your conveyancer, tax office or financial advisor before signing anything.
Maintenance and management are computed as a percentage of gross rent. Some property managers charge a percentage of collected rent (effective gross income) — adjust the percentage to compensate.
The model is monthly and linear. It doesn't model one-off capital expenditures (roof, HVAC) — reserve for those separately, typically $200–$400/unit/month.