Complex sentence: Interest payments are added to the capital throughout the term of the loan, which is then repaid by selling the property when the borrower (s) die or move out (perhaps into a care home).
Split into simpler sentences: Interest payments are either rolled-up on top of the capital throughout the term of the loan. The loan is repaid from the proceeds of the sale of the property when the borrowers die or move out (perhaps into a care home).