I understand how the OP feels. First three I bought, I didn't know what I was doing. Lots more problems than I thought. And I'm really glad you posted this here... most of the people on this board love ownership and don't really understand how daunting it can be sometimes.

Guessing by the games you bought, they were on the cheaper end of the pinball price spectrum. I bought cheap for my first three (F-14 Tomcat, Close Encounters of the Third Kind, and Jurassic Park).

What I've learned in the last year in this hobby:
1. They break. All. The. Time. It's part of the ownership hobby. But quite unexpected if you went in with a small budget. It was for me.
2. You have to buy a *lot* of tools, that you have to mail-order. And even then, you have to make runs to the part store for hardware and such. You also need to have a good way to lift the machines when you need to level them and move them around yourself. Even if you have a toolset for working on your car, you're looking at around another 300USD in parts/tools at a minimum. Even more if you buy nice tools. And sometimes you have to build/mod tools yourself to get stuff working or to even fit in the game.
3. You need to have time and patience to fix them. It takes work, genuine work. Which is super-frustrating if you are new to the hobby, because the whole point of pinball is to *play*. I found it demoralizing after a long day of work to come home to more work.
4. Best thing I've found is to go over and help some pinball friends fix their machines to get comfortable with the work. You help them with grunt work, they teach you how to do it right and fast. I'm starting to get the hang of soldering.
5. You need to have a good environment for it. An old apartment is a pain in the rear to have with pinball or with playing pinball as a hobby. My neighbors complain when I play my single EM, at 3PM, on a Sunday afternoon!
6. Buy a pin to your technical strengths - if you are good with electronics / board work (I grew up working on electronic kits), get something with rock-solid mechanicals (like early Gottlieb SS machines. My research has shown they tend to be more reliable than Williams mechanical stuff, and I had very few issues with my System 1 mechanically wise. Many of the time when you hear about people upset with System 1s, its because they are scared of circuit boards and the connectors, and those just weren't a big deal for me. Getting flippers rebuilt though, at the time, was kinda spooky for me. To each his/her own.
7. Tangentially related - buying arcade or VG cabinets can actually be easier and more reliable than pins, I've had nothing but decent performance from my Battle Balls arcade game. It was cheaper too.
8. If you are in an area with route games, go play them instead. They are cheaper than owning, if you look at out-of-pocket sunk cost. Most owners only play a couple hundred games on their machines in the time they own them. If you do the math, 50 cents x 300, or even 1USD x 300 is significantly cheaper than owning the machine, and frees up your finances to do other things with. Yes, they may be unreliable, but making phone calls to the operator and spending quarters is still cheaper than ownership for out-of-pocket sunk cost.

Also, I'm going to say this in bold because not many people are saying it: <b>There is more to pinball hobby than ownership!</b> My first attraction to pinball was competition and skill-building. That, I absolutely love. Meeting cool designers, like George Gomez, Steve Richie, John Borg. Going to shows and seeing interesting people, playing interesting games. Playing in tournaments, honing your skills. Playing on route and figuring out what person put their initials on the machine. Those things were much more important when arcades and locations were around, and that was the original environment pinball was designed for.