the OP brings to the market a fixed rate mortgage, where the size of the mortgage can bind to a fixed interest rate of up to 25 years.
the Loan can be paid ahead of time back, without a separate compensation, the OP told the bulletin.
the OP's in the model fixed interest rate throughout the loan period.
if you wish to the loan can also pay back earlier than planned, without costs, and the loan period can keep the grace of the normal procedure.
the Customer can choose a fixed interest rate also for only part of the loan amount.
OP offers fixed rate mortgage, only the owner-their customers.