Is it permissible to purchase goods for five thousand dinars and sell them to the buyer for eight thousand dinars in installments, based on the principle of murabaha to a party ordering the purchase, in order to avoid the suspicion of usury?

It is permissible to buy goods for a colleague and sell them to him in installments after acquiring them and bringing them under the seller's guarantee. It does not matter if the last installment is larger or if the amount paid by the buyer is the same as what he would have paid for an interest-based loan if he had changed his mind, provided that the seller owns the goods before selling them, and that the price does not exceed the agreed-upon amount at the time of the contract. The prohibition of Riba (usury/interest) and the difference between the two transactions must be explained.