I haven't read all of the posts so someone may have mentioned this before. But a couple of thoughts. Don't buy new in box pinballs, as they will likely lose some of their value at least in the short term. They are also very expensive initially as compared to used machines.
Start to learn how to do basic repairs. At a minimum, learn how to take apart a playfield, wax and rubber a game and possible install LEDs. Begin to learn how to do simple repairs - replace a flipper coil, replace drop targets, find and replace a bad transistor on a circuit board. Install a new battery holder, etc etc.
Then you will be in a position to buy a cosmetically nice game which needs some repairs or cleaning, and you can get it a little cheaper. You will get good enough that eventually you can buy cheap broken machines, fix them up, and either keep and enjoy them or sell them for a small profit. Do that a few times and you will have enough to buy another machine. Meanwhile, you will have a steady stream of different pins coming into your home for cleaning, repair, etc, keeping things interesting.
If you don't have much cash to start, pick an early digital machine for your first purchase like an early Bally, Gottlieb or Williams from the late '70's-early 80's. Many of these are fun to play and can be had in non-working condition for $300-700. Repairs are often fairly easy and the end result is a fun game worth maybe $1000-1200.
If you decide to go this route, I am also in eastern PA. If no one else is near you, you can always reach out to me for advice on how to make various repairs. I'm always willing to spend some time helping someone trying to learn. I consider it paying back a lot of guys over the years who helped me out when I didn't know a resistor from a diode!
If you don't want to do your own repairs, then there's no easy solution except money and lots of it based on today's prices!