Most of my pins are keepers. I bought them to play. I did sell my first game, my only EM, which was a WMS Aztec (so ‘75 I think). I fixed it so everything worked and even made a plastic for it that was broken when I bought it. I sold it to a guy who was making a 50s themed gameroom and wanted an EM with a chime unit. I so regretted that sale. It played fast for an EM and was a Blast.
The other game I sold was an F14 Tomcat that I bought to restore but never finished. I bought and built a Firepower for about $100 15+ years ago. It was junk, but I was able to fix all the boards and then retouch the playfield so it was acceptable enough to sell. It played well. I’ll buy another FP someday, but it will definitely cost me more.
Finally the game I’ve had the longest is an early production TZ. I rebuilt the HV on the DMD board twice. I got fed up and installed a Pin2DMD board which I recently got from Ptolemy and I really like it! It suits the game in B&W and doesn’t stress the game boards. I run it (and other mods) off a separate 12v supply. I’m not selling that game, it’s too much fun to play.