There are many many guys with 3rd gens with over 200,000 miles and counting. They are solid vehicles, if cared for. Make sure that the maintenance was done. Also, does it have a push button 4wd or lever? Either way, test out the 4wd on a dirt road (not on dry pavement). Does it have a locker? It's the button to the left of the steering wheel maked "R/R Lock". Test that out, too.
Look under the vehicle to see if there are any leaks. If it looks like a solid car to you, then go to a Toyota dealership or an independent mechanic and get a PPI.