Jeff, I've heard the same flat fee auction commission also. As an example, I can understand how the "69 Z28 thread for $112,000" subject of this thread is possible. Two bidders that are partners in any car can bid each other up to sky's the limit, knowing with the flat fee arrangement, they won't be having to pay the seller&buyer commission. Their hope of course is that some sucker will jump in and bid at those high numbers. But if no one does, after the auction they still own the car and can advertise it later as a car that sold for $112,000 at auction.
I wonder if this has happened to a number of these unrealistic car sales price. It seems we may not know what were true sale prices here. Is $400K for a street rod a real sale? Why pay that as isn't it possible to get one built for less than $100K? Things don't seem right here, in my opinion.