They have without doubt offered me the most for used cameras and lenses, and their prices for used equipment are also very nice.
I guess they operate on a much lower overhead than Mapcamera et all. Their HQ is in a grungy area, to be sure.
Once Japan (if) opens up, I can heartily recommend Fujiya.
As an example, I recently bought an af-s 28mm 1.4e Ed from yahoo auctions for ¥123,000. It was fine, but didn’t focus that well on DSLR bodies. Sold it to Fujiya for ¥124,000 :-)