20" wheel (kids bike) Scott Roxter MTB

This thing has been so good. Brenner outgrew it. Nice soft Kenda Slant Six tires (tubed). Mechanical disc brakes. Everything is true and good.
In my experience this is a good size for a 6-7 year old child unless they are preposterously tall.
It comes with a tarck sticker already installed!
i believe this website has the right specs: SCOTT Roxter 20 Bike green

the new ones cost $700. given the lack of available bicycles i will start the bidding at $500? i have no idea if that is reasonable or not. someone please tell me if this is insulting.