I set my machines to quarters. Actually I'm having trouble figuring out how to set my STTNG to just 1 quarter per play But, to be clear, I don't charge anyone. I keep a jar of quarters next to the games folks can use. I do it mostly for nostalgia. It just feels right dropping a quarter in a machine to play it. Plus, it's a bit like a savings account that way. I had $200 saved up in my Ms. Pac-Man I used to help pay for the repairs to my Space Duel.

Charging anyone to play, though, I do not. If they want to drop their own quarters in though, I won't stop them It's also a good way to not let, say, little kids play a game I think they might abuse. I just hide the quarters and it's a done deal.

Hah using a coin jar as a maintenance reminder is a really good idea!

As far as the $0.25/play agreed. I ended up having to upgrade to the latest revision of the firmware. Fixed a few other issues, so it ended up being worth it.