Home Purchase Financial Planning Simulator

Estimate the cost of buying and holding a home

Enter the purchase price, down payment, loan amount, interest rate and term. Compare the estimated monthly repayment with your available cash flow. Budget separately for acquisition costs, building management and reserve fund contributions, property tax and a possible future sale. This is a planning estimate, not a lender’s approval or a tax calculation.

Variable-rate loans: five-year and 125% rules

Some Japanese variable-rate, level-payment mortgages review the monthly payment every five years and cap an increase at 125% of the prior payment. Terms vary by lender and product. The rules do not freeze the interest rate or forgive interest: when rates rise, more of the payment can go towards interest and the principal can fall more slowly. Check your own agreement, including what happens after a prepayment.

Frequently asked questions

Does the five-year rule fix the interest rate?

No. The rate may change under the loan terms even while the scheduled payment stays the same.

Does the 125% cap cancel unpaid interest?

No. Review how your loan handles accrued interest and the balance at maturity.

Is the estimate a mortgage offer?

No. Lenders assess income, other borrowing, down payment and the property independently.

For an example of product-specific rules, see the lender’s explanation (Japanese).