What is the permissible শরعي way of conducting deferred-payment sales (installments)? Is it permissible to determine the price after knowing the buyer's preference for cash or installments, or must both prices be presented together? And should the installment period be determined before setting the price, or vice-versa?

If the price of the commodity, the method of payment, and the value of the installments are agreed upon at the time of the contract, then selling by installments is permissible, even if the seller increases its price in return for the deferred payment. The determination of the price and the duration is left to the agreement of the two parties, and guidance may be sought from the prevailing market price at the time of sale.