mine are all about suikoden. i found the prima strategy guide for the original suikoden in a box at Vintage Stock in Joplin, MO, for a few dollars. i didn’t know at the time that it was rare but i loved the game so i grabbed it, then years later searched it on ebay out of curiosity and found that it goes for more than $100.
then at one point i found a copy of suikoden II (the game, not the guide) on the gamestop website for something like $60, which at the time it was already going for well over $100 on ebay. impossible to imagine this happening now. i believe it was local purchase only but i called the store and they agreed to mail it to me. of course the game goes for over $300 now, so that was a super lucky find. or we might call it a Rare Find (suikoden reference)
my biggest regret is somehow losing the suikoden II strategy guide, which also goes for over $100. could be at my parents’ house somewhere but i can’t find it :(((((((