Muhammad bin Khazim al-Darir محمد بن خازم أبو معاوية الضرير · The Book of Financial Transactions

"It was forbidden to us for a town-dweller to sell for a desert-dweller." (Sahih )

the Messenger of Allah prohibited lending on the condition of a sale, or to have two conditions in one transaction, or to profit from what you do not posses.

"The Messenger of Allah caught up with me when I was riding a bad camel of ours, and I said: 'We have a bad camel, mare's the pit! The Prophet said: Will you sell it to me, O Jabir?' I Said, 'No, It is yours, O Messenger of Allah.; He said: 'O Allah forgive him; O Allah, have mercy on him. I will buy it for such and such, and I will lend it to you to ride until (we…