Last night I was going through my collection and I started figuring out how much I bought some of them for...
I found Castlevania: Symphony of the Night when it first came out used, but in mint condition, on the used rack at Software Etc. for $20. Then the game disappeared for a bit and when people were trying to find it all over again, people were selling the damn game for upwards of $60 on eBay.
This weekend I went to the swap meet and found a mint copy of 7th Saga on the SNES for $5. It was still in its original box too even if the box is a little frayed around the edges. Coincidentally, this same vendor is the same one I bought Killer 7 from for $10, JSRF for $5 and my Collector's Edition tin of Marc Ecko's Getting Up for $15 from.
Also, I don't know if this would count, but I also recently bought Samba De Amigo for the Dreamcast for $5 + $5 in shipping... When the game arrived, I realized that it shipped with the maracas! The same item sells for
upwards of $75 plus shipping on eBay! Holy fucking shit, that's the best $10 I ever spent on a game~
There's nowhere I can't reach.