Ruling on the agent taking an amount in excess of the price of the item without the principal's knowledge

Question:
One of my friends gave me ten thousand Egyptian pounds to buy him a car. I bought the car for the mentioned amount, but I gave it to him for eleven thousand pounds, that is, with an increase of one thousand pounds. Is this amount, which I considered profit, lawful or forbidden? May Allah reward you with good. Since I have experience with cars, as he says?

Answer:
This one thousand is forbidden for you; it is not permissible for you. You must return it to its owner unless he permits you to keep it, since you did not inform him, and you only told him that you bought it for eleven thousand. This is forbidden, an abomination, deception and betrayal. You must return the one thousand to its owner unless he permits you to keep it. We ask Allah for safety, and we ask Allah for guidance for us and for you. Yes.

The presenter: May Allah reward you with good.