The Precepts of Advance Payment Transactions
2141. A person may not sell a commodity acquired by offering advance payment, to a person other than its seller before the end of the stipulated period. In fact, obligatory precaution dictates that he cannot even sell it back to the seller in that period either. There is no problem in selling it once the period has expired, even if he has not acquired possession of it.
In the event that he sells it to the seller in return for a payment that is of the same kind as the payment he made, he should not sell it for a price that is greater than his payment.
As for a commodity that is sold by weight or volume, it is not permissible to sell it before acquiring possession of it. However, if it is not sold for a price that is greater than its price, there is no objection to it.
2142. In a transaction involving advance payment, if the seller delivers the transacted commodity on its due date, the buyer must accept it. If he delivers something that is better than what was agreed upon in the transaction, and it is considered to be of the same commodity, again, the buyer must accept it.
2143. If the commodity being delivered by the seller is of a lower quality than what was agreed upon in the transaction, the buyer can choose not to accept it.
2144. If the seller delivers a commodity that is different from the commodity agreed upon in the transaction, there is no objection to it if the buyer consents to it.
2145. If the commodity that was sold by advance payment becomes unobtainable during the period that it is due for delivery, and the seller is unable to make it available, the buyer can choose to wait until he makes it available, or he can choose to cancel the transaction and reclaim possession of the payment he made.
2146. If a person sells a commodity and agrees to deliver it after some time, and also agrees to collect its payment after a particular time, the transaction will not be valid.