I guess it depends on how it was maintained and the $$$ and the sellers honor ( IMO ). At about that mileage, I will have already replaced the chain, several oil changes ( every year ), the track will next at about 7K along with any studs they will be shot, several belts,hyfax, track clips, boogie wheels, skags, drive shaft bearing ( make sure the speedo works ). I would think 120# for the compression would be good, the closer together both cylinders are the better. Just for some examples. Look at the bulkhead & see if it was hit or is kinked along with the front heat exchanger if it has studs.I usually try to sell my stuff at a bargian, I don't want anyone buying anything from me and not being happy. If there are things that need replaced I will bring them up to the buyer. Sleds aren't worth much after the 1st year or 2 at most. I don't expect everyone to agree with me especially with the track thing but I have just went thru 3 ripsaws, all on sleds with 5-8 k. I would say that if you go to buy that sled with the year & miles is worth about 1/3 msrp for an estimate. ( I don't want everyone jumping on me ) but that is close to the truth.