Going to the Edinburg forestry auction? I was gonna attend, but I'm help someone move. I have been to a few before. It is mostly wiped Davey stuff. Seems like there are some deals and then some of the stuff goes for way more than what I would call a good deal. My buddies dad has a mid 90's F-250 4x4 that he bought for under a grand and it is ready to go right now for plowing. He didn't put much in it. The old chuck and ducks go for 300 to a grand. Anything that has a feed wheel will be bringing at the very least 2500 bucks. So guys there just buy them for a few certain parts and scrap the rest. So watch out for them.
I don't think the lack of having tires on the chipper is gonna make a difference in the price. I doubt you are the only person thinking about bringing extra tires too. A lot of hillybillies and tree guys can use their mind too when loading stuff, so a having a loader there is moot.