You planning on buying a used snow go? It can be dicey. Some people ride their sleds like idiots, then try cover it up and pawn the resulting wreck to someone else. While poking around, I found this handy dandy checklist online for checking out a used snowmachine.
Speaking of, I'm thinking of buying one myself. A tundra would be nice - reliable, lightweight, fuel efficient. Good in mountains. That, or an RMK 600. I'm looking for light. It's probably a bad decision at this point - that's why I hadn't done it yet - but it'd be neat to not have to borrow someone's junker anymore.