While those posts may sound harsh... I agree. You have to pay to play. And these older ATC's, while they can be found cheap, are not cheap to repair or maintain. Thats just the way it is with something 30 years old. LOL
There is cheap chinese quads out there, i know some will argue but still, that are a far better choice to get a kid riding. They are cheap compared to having to repair one crash on a classic ATC and scrounge
parts. Get a cheap chinese quad, let him beat the crap outta it learning to ride, and then later you can decide to let him on the ATC. Thats how i would do it, and i'm a parent of three fast moving boys so i speak from some experience. They will trash anything the get their butt on, not that they are reckless or such, but by sheer repeated use they will wear it down. I buy bike tires more then i buy bikes for them, they wear the tread off every summer because they ride till the wheels fall off!
I have an ATC90 that i let my oldest ride, but the other two are nowhere near ATC ready.