Buying a house by loan is a loan agreement signed by the lender with the bank in the form of house mortgage. Lenders are obliged to repay loans in installments on time. When the lender defaults, the bank may apply to the court to auction the lender's house according to law to repay the loan. The intermediary is only the contact between the buyer and the seller, not the party of the loan buyer, and has nothing to do with the loan buyer and the loan bank. Therefore, the loan can't afford to buy a house, and the intermediary has no legal responsibility.