If you have a car get a dashcam. It’s more valuable than any insurance because it will definitively prove what happened when something goes wrong. Bonus: you can post videos of bad drivers doing stupid things on the internet for imaginary points.
If only there was actually a good car dashcam, but every time I go down that rabbit hole I give up frustrated. The quality (build, mounting, video, whatever) is shit in pretty much all of them, and the "passable" ones look like a web cam from 2005 still.
I've bought the N2 Pro from Vantrue a couple of years ago and I've been super happy with it. The quality is pretty good and it has actually capable night vision and parking surveillance. I've also bought one for my brother in law (who got into an accident just a month after) and one for my grandma. Not to sound like an ad, but these are definitely worth checking out even if it's an older model.
Definitely get one for your teenage driver. It keeps them honest and safe. And they will pay for themselves many times over if you get in an accident that wasn't your fault. It's like having your very own personal unimpeachable witness riding with you.