Useful next calculations
When to use this calculator
- Before buying, renting, refinancing or reviewing a property investment.
- When you want to compare cash flow, tax, yield or ownership costs.
- When you need a fast estimate before speaking to an agent, lender or adviser.
- When you want to see how a rate or price change moves the result.
A worked example
These are the example figures the calculator opens with.
| Input | Value |
|---|---|
| Home Price (A$) | A$300,000 |
| Deposit (A$) | A$30,000 |
| Mortgage Rate (%) | 4.5% |
| Mortgage Term (Years) | 25 years |
For those figures the calculator returns:
- Monthly mortgage: A$1,500.75
- Monthly rent: A$1,200.00
- Monthly saving vs rent: -A$300.75
- Future home value: A$628,133.38
- Total rent paid: A$360,000.00
- Total mortgage paid: A$450,224.31
Method & assumptions
This calculator models the total financial cost of renting versus buying a comparable property over a period you specify. For the buying scenario, it factors in mortgage repayments (interest and capital), upfront purchase costs, annual maintenance, and insurance. For the renting scenario, it models monthly rent increasing at an assumed annual rate, alongside the investment return you could theoretically earn on the capital you did not use as a deposit. The calculator does not predict future house prices or rental inflation — you enter your own assumptions to reflect your local market. It excludes emotional and lifestyle factors such as stability, flexibility, and personalisation rights. Results are most useful as a sensitivity exercise rather than a definitive financial forecast.
Common mistakes
- Using an assumption that is not supported by a current local quote, bill, statement or official source.
- Treating a generic estimate as a lender, provider, payroll or tax authority decision.
- Mixing monthly and annual inputs without converting them consistently.
- Testing only one scenario instead of checking how a cautious assumption changes the result.
What to do next
- Run a second scenario with a cautious assumption so you can see the downside clearly.
- Compare the result with the related calculators below before making a decision.
- Check current local rules, eligibility and provider terms before applying or committing money.
- Keep a record of the assumptions so you can update the estimate when a quote, bill or pay figure changes.