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..
Looks like i'm just getting it for my own amusement then! Ill have to find something else to site, it seems all of the prize redemption machines are booming.
Redemption machines are a nice introduction for kids to the pokies. Redemption would be the best method to earn onsite.