I'll take a stab at this... maybe someone else will have more to add.
Things to look for: What year is it? Obvious signs of heavy wear 'n tear. Signs of rust? Fluids topped up and clean? Sediment in fuel filter? Tire condition. Does it start and run smoothly, both cold and hot? Play in steering? Play in front axle (particularly if it has a loader)? Gear noise? 3pt raises and lowers properly? PTO working? Is it gear, GST or HST? If it's gear, how is clutch? Brakes OK? Any signs of heavy mechanical repair (such as bolts and nuts that have been opened)? How did dealer come to have it (was it a trade or what)?
Like: Good power, stability, very reliable, nice mix of comfort vs. performance, sips fuel, easy to operate.
Dislike: Not much. No cup holder. Lacks skid plate protection for rough brush.
I have 4610, not 3710, but they are much the same except different engines and front axle.