Silicon Valley equity-gap planning

Assumable Mortgage Blended Rate Calculator

Combine the seller's existing loan with cash and a possible second loan, then compare the resulting principal and interest payment with a new first mortgage.





Equity gap$600,000
Second loan needed$350,000
Weighted note rate4.57%
Combined monthly P&I$7,754
Comparable new-loan P&I$7,901
Estimated monthly difference$147 less
Compare the complete payment and cash requirement.

Principal and interest only. The weighted note rate is not an APR. Taxes, insurance, HOA dues, mortgage insurance, fees, reserves, and closing costs are not included.

Why the Second Loan Changes the Decision

The assumed rate applies only to the remaining first-loan balance. When the purchase price is much higher, the equity gap may require cash or higher-rate second financing. A shorter second-loan term can also increase the combined monthly payment even when its balance is smaller.

Confirm whether secondary financing is permitted, how the liens will close, and whether the buyer qualifies for both obligations.

Educational estimate only. Financing availability, terms, and approval vary by lender, servicer, program, property, and borrower.