get yourself a cheap office type chair, then get spare hub/spindle
then figure a way to fuse/mate the 2 together. then you can bolt a wheel on & be able to spin it & do all kinds of stuff..
in terms of repaing scrapes & gouges it depends on the finish your going with. I have see people use JB weld, i have seen people use a body filler meant for metal, i have seen people use the liquid metal(2 part epoxy type setup stuff)
stripping old paint, aircraft stripper works prettty good.
I should have a thread up detailing a whole R&I proceess on a set of wheels & 1 of them has a huge chunk missing from it