Hello, geo....
It's generally best to not get in a hurry when tractor buying.......but, I guess that maxim applies to buying just about anything. I looked, perused, sniffed at, dickered with, and kicked tires for about 2 years until I found mine and she was a charity case that just didn't have that "shine." Got her for a song and put a little money into her where it counts and now she's a champ.
Too that, in general, tractor auctions have a less-than-desireable aura about them. Why would a tractor need to go to auction if it was a sellable item for the owner on the market? When you say the little Kubota was rather rough at $8700 that's why it was at the auction house and not on a dealer lot...because they were having a hard time moving it at whatever price they were asking for it and wanted to be rid of it.
Many years ago a monied gent out of the Metroplex bought a ranch in our area and by word of mouth he called me one day about (among other things) coming over and helping he and his new foreman with the equipment he'd bought for farming. He'd gone to an auction somewhere and made that house's fiscal quarter with the questionable iron he'd bought up......IH 1586 tractor that he thought was a steal at $8500 along with a leaking turbo, clutch in name only, interior that looked like a mountain lion and a bear had fought a death match in, hydro outlets frozen, hydro controls that would not remain engaged for any period of time, bad tires all the way around, non-working heat/ac. That poor tractor needed a good $10k worth of work to be a reliable unit for his plans. Often times, that is what you get at an auction.