Happens at all auctions, about 15yrs ago we had an estate auction for a friend, one of the lots was a set of taps and dies, new unused, the sold for $NZ 300, they were available in Christchurch (NZ) for $NZ249.50, and a few other things went the same way, some to the same vendor. There were some bigger items that bought good prices too, the guy was a collector of Caterpillar machines, such as a Highway Patrol road grader, D2 Dozer, and others.
Ian S C