When looking for pins, also remember that "HUO (Home Use Only)" often means "never been waxed, rocking the original rubbers, ball might be a little rusty, thank god it probably has low plays"
The majority of pinball owners I know don't have a clue how to work on them or properly maintain them. "Just shopped out!" often means "recently wiped off with a semi-clean rag".
I helped my inlaws pick up a pinball just last spring. The listing was on ebay, but ended up being about 10 minutes from my house. They came for a visit all excited about this "extra clean" and "shopped" machine (I told them what that word SHOULD mean), and it was a fairly popular machine (World Cup Soccer). We get to this guy's house, if you can call it a house. In an area where the average home cost is around $225,000 and that gets you a pretty nice house, this place was recently bought (by them) for over $1.1Million. So a very nice place.
Anyway, we thought, this will be a gem of a machine... Nope.
The guy said that when he bought it 10 years ago, it was fully gone through and was 100% perfect. THAT was his idea of "shopped"... Something done 10 years ago.
I swear that this thing was left in a garage or back room of a basement without the glass on it for about a month, and then played. At least from the looks. It was DIRTY. A lot of the lights no longer worked. There were broken plastics, one of the flippers was malfunctioning, etc.
I asked about the broken plastic pieces, and he said that he never knew about anything ever breaking, so either he was lying, or his 100% perfect machine wasn't so perfect.
With all of that, as some pricing information from recent sales, we were in a good position for some negotiation.
They were asking something like $2,300 "firm" but after listing all of the things that the machine needed, and the elbow grease to clean it all up, the guy sold it to my in-laws for $1,300. I created a parts list, and we ordered everything, and then spent a good portion of a saturday stripping down and cleaning the playfield, replacing bulbs and broken pieces, rebuilding both flippers, and giving it a good wax, and replacing the glass that had some big scratches in it. The parts came in at about $350 shipped, including a service manual and a couple of "fun" items like the keychain piece, etc. It now looks and plays extremely nicely. Definately a good buy in my in-law's mind.
So yeah, "shopped" means that at one point it was looked over. That could have been a month ago, but most likely was a few years ago.