You need to find out about license requirements, and make sure you have insurance. If your machine catches fire and burns down the place, you better be insured. If the machine falls, even through no fault of your own, and lands on a kid, you better be insured. If a kid gets electrocuted because of some goofy fluke (or from him doing something stupid), you better be insured. You will take the hit for it. Be insured through the gills or you are asking for it.

Also, do not expect to make any money. There will be very little earnings, which then must be split with the location. What is left will more than be taken up in parts, maintenance supplies, etc. Plus consider all of your time cleaning, waxing, fixing, etc. And expect the 1am phone calls demanding that you come fix your machine. One broken part can easily wipe out your earnings for a month or more.

Maybe I am making it sound worse than it will be, but be prepared for these things. If it was easy and there was money to be made, pinball on location wouldn't be all but dead and we would still see arcades in every town. There is a reason those things are gone. I'm not trying to be negative, just realistic.

There are many threads about this on RGP also with much input from existing operators and those who have done it in the past. It's a pretty bleak looking venture, but if you have the time, money, and ambition to "waste", go for it. Just don't expect anything in return...do it for love of the game only.