My Ford F250 with Tommylift and enough ratchet straps.
Smartphone with browser to check details on machines. Some are out-of-production and parts are NLA; no matter how cheap, it could be scrap iron if a critical piece is missing or broken.
Always go with a friend and give him orders in advance to slap the **** out of you when you're getting into divorce territory with the bidding.
FWIW, know your machines and inventory the parts and tooling. At auctions, sometimes it's just carelessness, but sometimes, it's enemy action; auctioneers and their staff have been known to to help a buddy and screw the seller and the other buyers by separating or hiding stuff which should be with a machine or vehicle.
If you're really interested in a vehicle or a machine and it is missing tooling, parts or controls, look in every box and cabinet in the frickin' building or lot.
At a school auction, there was a machine missing some essential parts. An hour's search located them in an early-lot-numbered box of tooling and accessories which I recognized as belonging to the machine with a later lot number. I told one of the auction company's staff it should be included with the machine. "Nope, once a lot number is assigned, it stays where it is." I suspected conspiracy, but was prepared either way.
Early in the auction, when the box of tooling and accessories came up for bid, soon only one other guy was bidding against me; and he was very annoyed. We ended up with me paying twice what the tooling was worth, but then with me ultimately getting a bargain on the machine for half what it was worth because I now had all the missing parts.
Bottom line - at auctions, trust but verify carefully. In the rush of checking out, stuff can disappear. If you buy a box lot or a tool box with some important parts or tools in it, take a cell phone photo and confirm the inventory when you are checking out. Same with machines; don't leave any essential parts.
jack vines