Calculate your break-even point before you sell house end of fixed term mortgage by comparing your current monthly payment against the new rate your lender has quoted. If your payment is jumping from £850 to £1,400 monthly, that’s £6,600 extra per year. Multiply this by how long you plan to stay, then subtract selling costs (typically 3-4% of property value including estate agent fees, solicitor costs, and EPC). If you’d pay £33,000 more over five years but selling costs £12,000, you’re £21,000 better off moving….