mjc3333 & others,I have cc but no bill acceptors. my cc usage is about 15% per month. I still get quite a few people bringing their own quarters. bill acceptance in the bays would not be a good idea in my area (vandalism). Also it would defeat the Vac it Up all together having to go to each bay to empty.
25+ years ago I installed orange tubing -from local nat gas supplier. One piece from trap to vac connection then one piece with a bend to slow the coins down into the safe. Not one smash through yet ! Now that I said that, I better keep my fingers crossed.I've ony worked on one system - they removed the old safes completely and just used drain PVC 90 fittings at the bottom. The genius who did the retrofit just hard-plumbed it all, and when a motor failed and it all clogged up I cut the PVC and used rubber couplers to reconnect it so it could be serviced easily if it clogged again.
You want to use hose or rubber flex-conduit anywhere there are bends (after the first 90 under the meter box). The coins will eventually smash through even Sch. 80 PVC and gray conduit sweeps.
If I did this, I'd still want a safe with the PVC 90 inside.
I was at a wash with metal tubing run overhead for the lines - it made an amazing racket.If not using gas pipe/tubing,I would use flex only at the bends so that any future repairs would be easier.