We do $1 for all new games (6 for $5). This is anything brand new and stuff like GOTpremium, FullT, Hobbit. Expensive games that cost more to maintain and to buy.
Aside from that, standard pricing is newer = $1 or 3/$2
New but around for a while or nice refurbished B listers from 90s = .75 or 3/$2
pre-DMD = .50
EM = .25
Reality is that while most collectors on Pinside have no problem owning 10, 20, 50k worth of machines, most will say they are pretty cheap when it comes to paying for pinball on location.
You are definately low balling your self BIG time. You have a solid and largely new colleciton which I assume plays well. You need to up your prices if you plan to keep them running well and actually cover costs. At your currnet 3/$1 you can expect to be burnt out and broke in a year. 33cents per play - taxes - split with bar - minus insurance - upkeep (dont event think about your time to maintain) and you are likely looking at .08 to .10 per play (and that is being generous). For a TWD that means 45,000 plays just to your break even point, and you are still worjking for free.
Something else to keep in mind is how much pinball cost in the early 90s when pricing was agressive and there were pins in every bar and then inflation.
.50 in 1994 = .80 in today dollars.
Even at .75 or 3/$2 players are getting a bargin compared to 1994.
The reality is that if you want to operate pinball for the long haul then anything less than .75 and you are setting up a failing experiment. This experiemnet is played out all over town for us. There are a few other operators of pinball (they mainly do grab machines and gambling stuff for the real business) and some charge .25 or .50 per play on newer games. Their games are broken, black from dirt and not worth playing after 2 months on route. They really have little choice if they keep the pricing the same. It will never make sense for them to maintain those games since they have priced them so low.