Core is Dave is risking HIS OWN MONEY on this. Auctions are Voetstots, meaning there is no warranty on the stuff, either implied or actual, and no return on them for any reason, as you are deemed to have bought after inspection and accept any defects or non working as part of the deal.
auctioneers do not have either the time, skill or any reason to actually test the stuff they sell. they are in the job of determining a "Fair market price" of the goods on each lot, and the work involved on each lot is pretty much the same irrespective of the actual amount of stuff on the sheet. If they see there is a lot of small lots from a same seller they often will consolidate them into larger bundles, as this both lessens the amount of time spent doing the suction and decreases the commissions paid by the seller. These typically are a per lot cost, with a variable commission on the sale price as well. Thus they will not sell as each, but will bundle till it fills a pallet typically for movable stuff. You might find a pallet of multimeters of assorted types, and this might have a large variety of different levels, but will go as a lot.
Typically if you ask an auctioneer to split out a part from a lot you will pay a lot higher price, often more than the rest of the lot as a whole. When I go to auctions and buy lots, I take the whole lot, and if I was only interested in a single item or two I often will place the rest on the next scheduled auction and get a part of the money back as well.