What is the ruling on the non-refundable deposit taken for reserving a property, considering that the broker bears expenses, advertising costs, and the loss of other sales opportunities?

The Fatwa's Summary:

The majority of jurists prohibit earnest money sales, while the Hanbalis permit them if the waiting period is restricted to a specific time. This is also the chosen view of thefiqh">Islamic Fiqh Academy and a number of contemporary scholars. If the buyer does not complete the transaction, the earnest money goes to the seller as compensation for holding the item back. As for the intermediary, he receives his compensation as a percentage of the earnest money or a fixed amount, according to the agreement. It is permissible for the questioner to take the earnest money and dispose of it as long as it is with the seller's consent.