Mortgage is a common method, which means that when the seller of real estate transfers the property that has been mortgaged to the bank or purchased through mortgage and has not been paid off to the buyer, the bank issues loans to the buyer to repay the original mortgage and mortgage loan, and redeems the real estate license, so as to handle the transfer, and the buyer will repay the existing mortgage or mortgage loan. In other words, the house that is still mortgaged is bought and sold again, and the buyer of the house continues to repay the mortgage payment of the seller.