I need some advice on this.

Stumbled on upon this robot toy, pic kinda related.
I have the same robot, but mine is in a worse shape. The box is still there, but also in worse shape. Mine is blue.

I am looking in selling it, as they tend to go for a quite some money. What price should I expect?
Where should I sell it?

The light is still functioning, the motor was broken, but I fixed it so now it works again (although it is a quite ugly fix).

Any advice or experience is welcome