In this sense, home buyers might worry about getting an affordable interest rate for their mortgage. This is where the decision between the freezing and the free float of a mortgage interest rate comes in. The setting of the mortgage interest rate begins with the period of setting the interest rates or with a fixed mortgage, but the borrower can exercise the possibility of taking a lower interest rate in the event of a drop in interest rates. The option to get the lowest price usually expires within 30 to 60 days. In contrast, a variable rate convertible mortgage (MRA) allows the borrower to benefit from lower interest rates for a few years before being converted into a fixed mortgage. Lenders may offer borrowers a floating option to set interest rates because they don`t want them to look around another institution or broker or finance their loan. .