I try not to use NADA for Snowmobile, Quad or Dirt Bike prices unless I see the prices locally on Facebook Marketplace, Craigslist and Newspapers are so out of what then I will check in just to see. But for the most part the prices around here have stayed pretty stable for the past 8-10 years. Even with the DNR enacting a trail pass requirement for those who live here. And that cost a LOT of people to quit and either sell their snowmobiles or part them out. Some pricing is a little high right now because it is coming into the season and we had 18" a couple hours north of me so people are jumping on that and that the UP in Marquette got hammered already for 2.5 days straight with snow and last I heard it was 20 some inches down by tuesday morning.
Just try to look around take an average and go from there. If it is too high like Bear and snowmoer said move on. Snowmobiles are always for sale. You can find them year round from people who want out or have issues especially in Nov/Dec when they realize Christmas is coming and that they can't afford that Xbox, PS5 or w/e the kids they have want.