Final answer:
The lending institution typically requires a buyer to sign a promissory note and mortgage at closing to guarantee loan repayment and to allow the property to be seized and sold if the borrower defaults.
Step-by-step explanation:
At the closing, the lending institution that loans money to a buyer usually will require the buyer to sign a promissory note and the mortgage. A promissory note is a written promise to repay the borrowed amount, whereas the mortgage is a legal document that secures the promissory note and provides the lender with a claim against the borrower's property if the borrower fails to meet the terms of repayment. This ensures that the lending institution has two forms of security - the promise to pay back the money in the form of a promissory note and the right to seize and sell the property, which is stated in the mortgage agreement, should the borrower default on the loan.