I come look at them once in a while for people who find me somehow and ask if I can help them.

I don't generally charge to come look and if I can fix whatever is broken in a few minutes with what's in my box then if you have some beer I'll take care of it. Beyond that it costs real money, and most of the time when someone has a problem like this the game is in pretty bad shape and needs quite a bit of work. I saw one that had a bad driver board channel along with an open on the switch matrix at the CPU board and had never had the power board re-done; it was dirty (power-wise) on the HV side, all original caps (and some were leaking badly), etc. I explained that I could take the boards back to my place, re-cap and go through them all, including re-pinning the headers, but for the cost of the time the owner would be pretty close on money to just buy new boards, and then he has new ones with a factory warranty and whatever upgrades have occurred in the interim; I also warned him that if he didn't fix the HV board he was going to cook his displays and those are a bit expensive -- as it was they were flaky but still working. I took care of a couple of quick things but it was obvious that completely fixing the game functionally was going to be a solid day's work -- at least.

When you get down to it the reason the games are in this condition is that they're pretty far gone and on a dollars basis it makes no sense to spend $500 in labor on a $500 game; when you're done you still have a $500 game with a badly worn (and in this case planked) playfield, displays that are in moderately-bad shape and similar, but you're out the other $500. Most people throw up their arms at that point and figure they'll play it once in a while in whatever condition it's in, and there it sits instead.