Selling a car for a car with an additional amount of money

Question:
Honorable Shaykh, if I sell my car to a person on the condition that he sells me his car, and I pay him a price above the value of my car because his car is more expensive and better, is this forbidden? And what is the reason for the prohibition?

Answer:
This is not forbidden. If you sell a car for a car, meaning you make the car in exchange for the other car, then this is fine, there is no harm, and it is permissible. It is also permissible for there to be some money with the second car if the second car is better; you add some money to the lesser one in exchange for the good car. There is no harm in the money.
What is prohibited is selling your car for ten thousand on the condition that he sells you his car for five thousand, meaning each one has its own price. This is the prohibited case because it is two sales in one sale. As for selling a car for a car, this is one sale, a single sale, and there is no harm in it.