Is one who allowed a car he rented in his name to a relative to be destroyed, after its repeated breakdowns and repairs at personal expense, sinful?

It is not permissible to destroy the car because it constitutes a waste of money, which is forbidden by Islamic law, and because the car is still owned by the agency, and its destruction is an assault on the property of others. The questioner incurs sin to the extent of her ability to prevent this person. If she was able to prevent him and did not, then she is sinful for failing to change an evil when she was able to, otherwise, there is no sin upon her.