I have fond memories of being dropped off at the local campground's arcade with my brother and sister and a fistful of quarters. This was pre-Pong, so the arcade was all pinballs, shooting and baseball games.
While we were still kids, a neighbor who ran a local pub gave my brother a pinball machine he had in his basement (I think he was replacing it with one of those new electronic machines). It was a Central Park, with a broken backglass monkey. We played it a lot, despite the lack of "deep" gameplay that more modern machines have. After several years, it stopped working and sat there in our parents' basement. Eventually, we each moved out of the area.
I worked in England for about five years and played all the pinballs I could find (from Soho down to Brighton, I must have played them all).
In the early 90s, I moved back into the area and I took the Central Park with the intention of getting it fixed. This was in the days of computer bulletin boards and I found the USENET group rec.games.pinball. I found tips on how to service the machine and (with supplies from "Mr. Pinball" Steve Young), I got Central Park working again! I even bought a NOS backglass monkey to ring the bell (which promptly snapped in half just like the previous one had done).
Along the way, I filled in an online form somewhere mentioning Control Tower as a machine I'd like to have. I'd never actually seen one, but I work in the Air Traffic biz and liked the sound of the theme.
A few years later, I learned of a local amusement auction held around the time of my wedding anniversary. My wife and I went and found (and loved) a Star Trek The Next Generation pinball. My wife suggested because it was our "glass" and "electronics" anniversary and the machine had been built the year we were married, it would make a good anniversary gift for each other! I bid and won it (relatively) cheaply (my limit was $2000 and it got very close).
More than 10 years after I had mentioned (and long forgot) that I wanted a Control Tower, someone contacted me -- they had one that they wanted to sell, did an internet search and my contact info came up (kids, remember: The Internet is forever). I gained the Control Tower and a Virginia from their basement, both in good shape.
Instead of Free Play, for the thrill of the thwack (earning a free game) I usually set my machines to multiple games for a quarter and used to give the kids quarters for helping out around the house. When my son was about 5 and his grandmother gave him a dollar bill, he asked if he could have a quarter instead because "what can you do with a dollar?"
I was running out of room so I lent the STTNG to friends (Star Trek fans) for several years. When I got it back recently it was non-functional, had water in the bottom of the cabinet, heat damaged Borg ship and two warped ramps (it had been stored without a tarp in a garage, in direct sunlight when door was open), the left gun was non-functional, the upper right flipper was loose, the backglass key had been lost and the coin door key was broken off in the lock. Many bulbs were out (one was broken and a couple wires were detached but most of them just needed cleaning). I've spent two months of my COVID-19 quarantine restoring it to full working order, something I achieved last week.
In fact, I decided to customize it somewhat as I don't intend to ever sell it (or lend it out again). I replaced all of the backglass bulbs and about half the bulbs in the playfield with LEDs. I also painted the cream-colored Borg ship a gunmetal gray and replaced the blue plastic windows with green plastic, cut to fit. See playfield image. I created my own pair of slightly oversized, magnetic-backed rules cards, using a STTNG font and an LCARS background (with smaller print "For Captain's Eyes Only" section describing how to switch Holodeck Mission to Poker or Breakout, how to start the Secret Mission, etc.).
I also added a cup holder :-)