This could be something that you bought for a higher price than what most people would guess based on the item, or it could be something you bought for a normal price that has gained significant value as time has gone on.
What made me think of this question is a LEGO minifigure I got with my “The Hobbit: An Unexpected Journey” disc. It is Bilbo Baggins in a blue coat that was apparently only sold in that movie box only at Target stores. Even considering the exclusivity, I would have guessed maybe $10-20 for such a tiny piece of plastic, but there are sold listings on eBay from $80 to $225. I could possibly even get towards the higher end of that number since I still have everything in the original box in good condition. It’s not worth a ton compared to some other items people may own, but I think most people would not expect nearly that amount.
I had a free book reward from Thriftbooks, which I used for a copy of Long Dark Teatime of the Soul by Douglas Adams. When it came, I was kinda bummed that some kid had scribbled on the title page, but eh, it was free. At least it was a first edition in otherwise good condition, I won’t complain.
As I was reading, I got a little itch in the back of my mind, and it of curiosity looked up his signature. Turns out, it looks like some kid’s scribbling
Probably why no one realized.
So I got a signed first edition, which goes for about $200, totally free.
WHAT. That’s crazy! What a story- great find!
A very Douglas Adams sort of occurrence, particularly fitting I thought.
I used to frequent a thrift shop that gave books away for free, I saw a copy of Cloud Atlas and thought it would be a good read (it was). I accidentally for the dust cover a little then looked at the title page, signed first edition. Not worth much, but cool nonetheless.