A bit about my pinball background; I'm fairly new to pinball machines.
We have a few pinball machines at work. It started with a Tales from the Crypt, and we've had that for about a year. So at the end of 2013 we wanted another machine, a Revenge From Mars, and it did not stop there because we got a new machine for about every week in January.
We did some mods on a few machines, and we fix them where we can. I even bought a
Star Trek: The Next Generation for myself. So far, I've gotten hands-on experience on multiple machines.
We started completely renovating the Medieval Madness we have at work. Swapping the playfield for a completely new one, sanding and repainting and restickering the cabinet, and clean and replace all broken plastics and assembly's. It turned out pretty nice and we are now dialing it in.
My first machine was a ST:TNG and I'm now trying to improve it. LED kit, borg ship paintjob, fixing mechanics, fixing electronics. The thing breaks down more often then I'd thought, but I like working on it, so it's not that bad.