What is the ruling on stipulating the return of unsold goods after a certain period, bearing the shipping costs, or destroying them?

It is permissible to sell another person's goods for a known wage or a percentage of the profit. This is called an agency (wakalah) or a contract similar to Mudarabah (profit-sharing partnership) or Muzara'ah (sharecropping). There is no objection to specifying a duration for this agreement.

It is not permissible to destroy unsold goods if they are still usable, because Islamic law prohibits wasting wealth. It is encouraged to donate them if their owner does not need them.

"Tasreef sale" (sale on consignment), which is selling a commodity on the condition that the buyer pays its price if he is able to sell it, otherwise he returns it, is forbidden because it contains an unknown exception and suspends the sale on an unknown matter. This contradicts the essence of the contract which makes the commodity the property of the buyer. Scholars have differed regarding the invalidity of the contract with this condition. The relied-upon opinion in the Hanbali school is that the sale is valid but the condition is void. Therefore, the buyer owns the commodity and owes its price to the seller, whether he is able to sell it or not.