I almost didn't buy a Grand Prix project because of the difficulty hype. I decided to bite the bullet, and bought a machine that had sat unused in a warehouse for over a decade. I had to used a leaf blower to clean out the cabinet.
With the help of Pinsiders, in a few weeks I owned a working machine that was a blast to play.
I can't vouch for the machine you were considering, but I think you can trust the people on this site to help you as much as they can.