Under normal circumstances, the amount of bank loans will be less than the value of the guaranteed house you provide. In other words, when lending, banks will consider the realized value of mortgaged houses when they cannot repay in the future. Moreover, the value of the auction is also very objective and will not be significantly lower than the market value. If it is really not enough to repay the mortgage, then according to the judicial interpretation of the Supreme Court, your other house has no mortgage, and the bank's creditor's rights to this house are just ordinary creditor's rights. Unsecured houses can be sealed up and cannot be auctioned, sold or paid off.