People often complain about such auctions. But that is because those grumblers actually want to be in first place for a dime and, moreover, do not know at all what they are doing because they are blinded by greed and faulty economy.
In the past there were never any problems at auctions because at the time they were only visited by professionals. And they knew the conditions and did not get carried away. When Porsches were auctioned at De Domeinen ex Police some forty years ago, that story was passed on to private Porsche enthusiasts. Which directly offered up to more than 100% above the traders. And since history always repeats itself ...
The auctioneer determines an opening bid. Subsequently, a lot of individuals who do not read the conditions (which are also on the sites) fully agree. When the lot has to be picked up, they find out that (depending on the project) 16% auction costs + 21% VAT on the bid + auction costs have to be paid. So what the 'lucky' buyer has to pay in the end is about 40% higher than the bid.
And that is swallowing if you have not taken it into account. Also annoying when you have overlooked the fact that the lots are being sold 'footsteps': No test drive, even starting an engine is impossible. And the guarantee is not talked at all, although there are arrangements for very strange conclusions immediately after the purchase. After all, a professional auction company also benefits from satisfied customers.
So visit the viewing days and complain immediately after purchase if there is reason to do so.
But stay away from auction sites where bidding itself costs money (although 10 or 50 cents per bid does not seem like much). You don't see auction sites like this as a customer, but as a dairy cow.