finding aftermarket parts for a t4 isn't the problem. It when you break something like a gear in the transmission that's no longer remaining in any warehouses. There's a lot of parts on that quad you wouldn't think of being hard to get until you break it and there's nothing around, and you're stuck retrofitting and modifiying other stuff to make it work. When you own a t4 you almost have to have 2 of them, one to ride and one for a parts bike. Because you just can't count on a machine that's been beat on for 20 years to be bulletproof reliable and never have any problems.
You may start by saying, $300, how can I go wrong? But about $2,000 into replacement parts, and it's still breaking down on you, and half the time your buddies ask if you want to go riding but you can't because it's broke, you start scratching your head and wondering "did I possibly go wrong with this deal?"
I speak from experience when I say that it sucks sucks sucks when you can't ride your quad because half the time you're fixing it or waiting for replacement parts. That's why i'm selling my warrior, all I ever do is spend money on it and fix it. If I left it stock it would have been fine, it's just that my warrior doesn't seem to get along well with non-oem products. So this time i'm buying a quad brand new (not some beat up thing that some kid ran into the ground like last time) and leave it completely stock except for skid plates, tires, and non-mechanical stuff (unlike last time, when I modded the sh*t out of my warrior and lost a ton of money and just caused myself trouble)
Enough of my rant though, good luck with whatever you decide guys