Also be sure to take a look at this thread:
https://pinside.com/pinball/forum/topic/how-to-not-get-ripped-off-in-pinball-vids-guide/
There's a lot of good info there to help explain how some of the scams work and how to detect/avoid them.
Buying (or selling) a game remotely is always going to carry some amount of risk.
Part of the reason that these scams have been working so well is that there is some pressure to act fast to avoid missing out on a deal. Unfortunately, that sometimes leads to rash decisions. If a deal is too good to be true, it probably is--so be cautious.
Since there are Pinsiders everywhere, some members have been checking for anyone who might be nearby to where the game is being sold and asking them if they would be willing to do a spot inspection to make sure the game exists and the condition is about what is actually described.
Mr Pinball maintains a blacklist, so be sure to check there for known scammers or aliases:
http://user.xmission.com/~daina/known_scammers.html