I've been using the Mr Pinball website since 2001. That 1st year I got burned on a guy selling NOS Gottlieb EM playfields. I contacted the Atlanta police which was where the seller claimed he lived. Police report etc. It's still listed on the Mr Pinball scam alert website link and updates show the SOB is in jail now. Forward to 2018. I have always had great results with wanted ads from other collectors. Bought parts and games and was always happy since lots of these people aren't on Pinside or RGP back in the day. Recently posted for a couple PF's and most responses were scammers. To protect yourself:

1) Do a reverse image scan on google. Take any pictures you're sent, download and click "images" on google. Download the pics and see if listed to a former sales ad or a pin website.

2) Gmail is the preferred Nigerian server.

The rest has been covered here like bad English, no phone contact number etc.

Sucks that a great resource is now being overrun. I have these dirt bags responding to my "wanted" ads on CL asking what my best price is for the pinball machine I want to buy only because I list in the selling area. Oh well, just be smart.