That's a tough call, there aren't a lot of used tractors out there. I was looking for 955 the other day, and I think there was less than a dozen listed at all of the Deere dealers, and only 3 listed on Ironsearch. The price would really depend on hours and condition. Maybe this will help, I have a 4300 here with FEL and Hoe, no snowblower, 500 hrs, in good condition, and we are asking $19,000. It is a lot newer than the 955 you are looking at, but very similar in size. My guess, if the tractor you are looking at is not high hours, (and what is average?) 1000 or less, in good condition, I would think it is worth $15k. If you find some on machinefinder, loader only, they are still asking 12 or so for them. If I had one to sell, I would certainly be asking for top dollar, because they are so hard to come by.
If you can get more info, we can try to pin it down closer.
good luck!
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