Cheapest second generation Mirai I could find is €9950 including VAT. It has scuffs all-round but no major or structural damage. Only 103k km.

This was a €71,000 car four years ago. That is 86% of the value gone. And you were driving around on very expensive hydrogen (compared to diesel and BEV).

> And you were driving around on very expensive hydrogen

That original owner was probably doing all those miles on the free hydrogen given by Toyota.