I speak to operators regularly.
Bottom line is that operating pinballs is a very risky proposition. You need video games to complement the pinballs. successful pinball sites are usually established arcades, selected pubs, movie centers and some family restaurants. A pinball on its own is not going to make you any money.
I had a operator in yesterday who just sold his route. There is simply no money in it, especially now that the price of NIB is unaffordable. As he said - "Spend $7000 - $8000 on a new pinnie to make $400 in your first week, $200 the next and then $50 for the next month.." He told me a great story about a sited "Old Chicago" - he removed it from site 5 years ago. According to the coin counter and his record keeping, it had made over $100,000 in earnings.
The days of making an earning on pinballs is well and truly over unless you own a timezone. Try a reliable machine in a pub, and expect $30 - $60 per week.. That might cover the public liability insurance..