They're unusual cars, and they're based on the Nissan Silvia. The Nissan Silvia is already a bit pricey secondhand because of "drift tax". I don't doubt the Le Seyde prices are tracking Silvia prices.
Hmmm... looking it up... there are only 500 Le Seydes in the world. Should have snapped it up. You definitely could have sold it for more than you bought it for.