Concur w/ Greg. my '02s have 130 hours on them, but I've done all the pre-season and post-season maintenance every year, and I keep records. I would not by a ski without testing it on the water. Do you have any watercraft maintenance experience or are you going in blind as to inspecting mechanical/electrical systems?
Problems (doesn't include routine mx or wear rings) on my '02
1. Replaced two j-pipes due to exhaust leaks (same ski twice)
2. Replaced both information centers due to water intrusion/corrosion. (That's a $600.00 part!)
3. Replaced one cam sensor
4. Replaced one MPEM ($250) due to loose AMP connector socket on MB.
5. Replaced one carbon-seal and boot. (not really defective; water was coming in from O.P.A.S. valve)
Then engines run great, and they don't use oil.
Steering and reverse gate cables will probably need to be flushed with lubricant.
With power on the ski, you can press "set" 5 times and any fault codes stored in the ECU will appear on the information center. Some codes are nuisance codes; some could indicate serious problems. You can see what those codes mean on the forum sticky.