In that case starting with obvious things that stand out to them will help, Steering wheel lock is one of them. You can never stop a determined thief but you can discourage some of them though methods like that. $40 on average for them.The entire car. I won't leave anything on the seat..
Aftermarket alarm systems may help and can be useful (especially the ones that notify you if someone messes with your car). That said, they can be hyper sensitive or go off for no reason sometimes leading to situations where you might ignore them.The entire car. I won't leave anything on the seat..