My seventeen year old son is currently learning to drive.

He will be off to Uni next year and won’t need a car full time. So what we have decided to do is for him and his Nan (who also lives in our village) to share a car. She doesn’t need one much, just from time to time, and it will be similar with him. They can then split the running costs – which will help him out.

So, a couple of questions so that I have some idea before calling insurance companies. I would anticipate his Nan being the registered owner.

1 – What might be the best way to insure them both? Separate policies entirely? Or him as a named driver on hers?
2 – Installing a black box on a shared car – how might that work? Is it active all the time regardless of who is driving, or is there a way for it only to be active when he is driving?
3 – The car would spend some time at hers, and some time at ours. Is that likely to be a problem with which is the main residence for the car?

Anything else I should be thinking of?

Ideas, especially based on experience, very welcome!