Repayment installments are usually the minimum interest due every month for the first ten years. (badcreditloanservices.com)
So you have around $ 500 in interest due each month right now, plus whatever principal you owe - say $ 300 in principal, if you have an $ 800 payment (before escrow, insurance, etc..) (money.stackexchange.com)
Your interest due each month depends on your principal balance. (themortgagereports.com)