shoRe: What is a 1997 M900 with 600mi on it worth?
As a point of comparison, I bought a 97 M900 this summer that only had 300 miles on it. I looked virtually brand new. I had the dealer put a stage II jet kit and some DP carbon fiber exhaust cans on it and it runs great. At the 600 mile mark it started to burn oil (noticeably) and I took it in and they put new valve guide seals in it ($200), but it's still using :-/oil. I would be very cautious if I were you. If it was sitting for that long without proper preventive maintenance done then there could be all sort of bad things waiting for you, amongh them being dried out/cracked valve guide seals, bad cylinders, piston rings, valves (rust, corrosion), bad gaskets and seals throughout, etc, etc. I'd take it to a reputable technician and have it thoroughly checked out. If I had to do it over again, I wouldn't.