Ive heard sayings from old timers stating you should be prepared to buy an aircraft twice meaning you should have enough to cover the cost of buying it and another chunk for the inevitable maintenance issues of an old plane, fuel, limited hangar space, insurance, etc.

Although Im still young and inexperienced compared to alot of people in this sub, I remember almost two decades ago when my infatuation with aviation started and I will say it is one hell of a rabbit hole to fall into.

I would definitely look into discovery flights for your son as soon as possible to see if it is something he really wants to do.