How much do you think a very used dm1 costs? The rims will hurt you when you grind.
Answer from your supreme knowledge is appreciated. 
About 15-20. If the rims hurt when you grind, that would be a turn off for me. The price would have to be pretty low.
A yoyo is worth what somebody is willing to pay. It could be $30, it could be $3.
Can it be fixed with some $1 (low grit) sandpaper? Or are the dents so deep that grinds hurt even after you tried to sand it?
I wouldn’t buy a yoyo that hurts on a grind.
My guess would be 20-30 dollars if you can fix the surface with sandpaper.
how much would YOU pay for it? that is the answer
im not sure. thats sort of why i made this post
I would say about 10-15 bucks
I think that you could probably find one for $20.