What is the difference between the permissibility of selling on credit—even though the price of the commodity is higher—and buying a house owned by the bank?

It is permissible to sell on credit at a price higher than the cash price, whether the seller is a bank or otherwise, as long as the conditions of sale are valid. It is forbidden to determine the price based on the time of payment (two sales in one). It is forbidden for usurious banks to lend with interest, as these banks lend the price of houses to the customer with an increase, which is a loan that draws benefit, and is prohibited.