What is the ruling on selling a car to a buyer who pays half its price to the seller, and then the seller pays the buyer the remaining half through a loan office, which the buyer then repays to the office with an usurious increase?

If the agreement between the car buyer and the loan office stipulates that the buyer orders the office to purchase the second half of the car with a non-binding promise to buy it through Murabaha, then this is called Murabaha to the one who gives the order to purchase. This is permissible, provided that the conditions of sale are met and its impediments are absent, meaning that the commodity enters into the possession of the office and delivery takes place, and the office bears the responsibility for damage before delivery and the consequences of hidden defects thereafter. However, if the agreement stipulates that the office pays the remaining price on the condition that the buyer repays it in installments with an increment, then this is a loan that yields benefit to the lender, which is unanimously forbidden because it is usury (riba). Thus, the transaction is permissible in the first case, while in the second case, the transaction between the buyer and the office is forbidden, and contributing to the coordination between them is aiding in sin.