Granny Flat Rental Yield & ROI Calculator
Explore rent, borrowing and expense assumptions. This simplified scenario excludes land value, vacancy, principal repayments and tax; it is not an investment forecast.
Editable scenario inputs
Tax deductions not calculated
Illustrative inputs only. Expenses use fixed presets listed in the FAQ. Vacancy, loan principal, land value and tax are excluded. A positive result is not a complete cash-flow forecast.
Granny Flat Investment FAQ
Read the assumptions and exclusions before using the results.
Does this establish a good investment return?
No. The ratios use the entered build budget, excluding land value. They are not comparable with a whole-property yield or a forecast of capital growth.
Which expenses are assumed?
The model assumes 52 occupied weeks, $650 annual insurance, $450 council costs, maintenance of the greater of $600 or 0.5% of build cost, and the selected management rate. These are illustrative presets, not market averages. Replace them in your own detailed budget.
Does it calculate tax deductions?
No. A project budget is not the same as eligible construction expenditure. Ask a registered tax agent and, where appropriate, a quantity surveyor to assess deductions.
What rent should I enter?
Obtain a current property-specific rental appraisal. The starting value is an example, not a local median or a promise of achievable rent.
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