There are insurance companies that will allow you to insure vehicles that belong to other people. Esurance is one insurance company that will allow you to insure a vehicle even if you have no 'insurable interest' in it. However, I do not know of any insurance companies that will allow you to insure vehicles from more than one household. If he and his vehicle are going to reside elsewhere, chances are your insurance company will not cover the vehicle. He will need to get his own insurance for his vehicle. In the meantime, if he is going to drive the vehicles of his friend's parents while he is residing with them, chances are they will need to list him as a driver on their insurance policy - or they are running the risk of their insurance company denying a claim if he is involved in an accident.

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