9. 1961 Ferrari 250 GT SWB California Spider
This car generated more during an auction than all 58 other cars put together. This special Ferrari was actually intended for an exhibition in a museum, but was languishing for years in a collection with around a hundred other cars. At one point, 59 of these cars ended up at an auction, where apparently some people were walking around with a very well-filled wallet. The Ferrari was sold for a massive amount of more than 17 million euros.
Auction: Arcturial, Paris, 2015
Price: € 17 303 905