I've never listed a pinball machine before but I find it interesting that I occasionally get flagged along with nasty e-mails about the price I have items listed for even when they're items listed for as little as $20.
If I think something is overpriced I simply don't buy it. I don't really think it's my job to "educate" a person on what they should ask for something they own. If you want to list an item for $1000 that most people usually pay $10 for then go ahead it's your stuff.