This might need some perspective: this is a $225 game. Any attorney actions by either side would swallow this up in the first hour.

If this individual wanting his pinball machine back persists, you might want to save yourself a lot of hassle and heartache. I would explain to him your position (out $75 and your time) and negotiate a reasonable price. Make "as is" a condition of return: I would not reassemble anything. Put all the parts/pieces/bits in a box and return them. Have him sign a release that absolves you from any further actions on his part. You can find these documents via a google search. Amend it as needed and then be done with it. How much is your time worth?