What is the ruling on selling a car in installments while it is mortgaged, and then selling it to a third party before receiving it and paying its full price?

The question addresses several issues related to selling a car, and the answers can be summarized as follows:

1. Agent Authorizing Another Agent: Scholars differ on the permissibility of an agent authorizing another agent. Since the sale has already taken place, it is best to follow the opinion of those who permit it, such as the Hanafis, or the opinion of those who state that a sale whose invalidity is disputed becomes effective upon payment of the price, such as the Maliki view.

2. Car Ownership: The fact that the owner has not finished paying the car installments does not affect the validity of the sale. Once the contract is concluded, he owns it and is entitled to sell it after taking possession of it.

3. Selling Before Possession ( قبض): The majority of scholars prohibit selling an item before taking possession of it. However, the Malikis and a group of others permit selling anything other than food before taking possession. The more cautious approach is to renew the contract after possession if possible. If not possible, there is no objection to following the opinion of those who permit it.

4. Deposit (الْعَرَبُون): If what you paid was a deposit in the known sense (non-refundable if the buyer reneges), then there is a prohibition against it, although the Hanbalis permitted it. However, if it was part of the price, there is no harm in it.

It is advisable to adopt the more cautious opinion in the future.