I run a bar here locally, and am also "employed" by my coin op operator. The first thing I can tell you is that route pins take a monstrous amount of abuse, whether intentional or unintentional , so be prepared to spend a very large amount of time or money fixing your pins (I spent at least 16 hours last week rebuilding pop bumpers, flippers, and replacing switches on a few of my machines, coupled with the cost of parts and shipping that adds up). Secondly laws vary from state to state, and sometimes from county to county regarding permits, licenses, and tax collecting. Thirdly the type of pin on location directly affects how much you will earn per month per pin. For example my newer Stern pins make more per month than my classic Bally/Williams due to the fact that they are "New" and I have to charge .75 to 1.00 per game to pay them off before I can make a profit on them. I can only charge .50 per game for my "Old" pins because they are "OLD" and random players will not spend more on classic games in most cases. Finally, change machines are a bit pricey and prone to jams and breaking, if you are placing your pins in a bar make sure that the location knows to have extra quarters in the safe and tills to accommodate their players if you can't provide a changer (which is another $500 out of your pocket to keep filled).
Now if you have the pins to spare, the time and energy, or the 8 to 20 grand to blow on 4 to 6 machines that might earn $200 a month each go for it, I'm a fan of exposing pinball to anyone and everyone that will drop a buck or two to try their luck/skill at the silver ball.
Scared you off yet?
If the answer is no, you are probably just crazy enough to make this work, and in that case good luck and good fortunes my friend...