Is selling goods in installments with an added profit, where the purchase is made directly from the store and the item is immediately delivered to the buyer, considered usury (riba) by means of deception?

If a merchant genuinely buys goods and they enter into his possession, he may sell them for cash or in installments, with an increase or decrease [in price]. This is not considered a trick to circumvent usury. However, if the goods are food, it is prohibited to sell them before taking possession of them, due to the hadith: "Whoever buys food should not sell it until he takes possession of it."