What is the Sharee'ah ruling on appointing someone as an agent to sell a piece of land in return for a charge; for example, I say to him: if you sell this piece of land for 20,000 dinars, you will take 1,000 dinars; and if you sell it for 21,000 dinars, you will take 1,500 dinars?

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu 'alyhi wa sallam, is His slave and Messenger.

Appointing an agent is permissible whether it is in a return for a charge or not. Nevertheless, the charge must be specified because to do so in return for an unknown charge is invalid. The Hanbali scholar, Al-Buhooti said, “Appointing an agent in return for an unknown charge is invalid because undefined compensation is not valid under the Sharee'ah. However, the agent's action (in such an arrangement) would be valid because there is a general permission to act. In such a case, he deserves the fair market charge because he has worked in return for a compensation that he did not (yet) receive.”

Consequently, the form of agency stated in the question is impermissible because the charge is unknown; will it be for 1,000 or 1,500 dinars?

Allaah Knows best.