What’s the best deal you’ve gotten on cars or parts

I traded even my 7 1/4 out of my duster for a 391 eight and three-quarter All I had to do was shorten the drive shaft
I got a new 650 double pumper for nothing
I had forgotten till I saw some posts
I answered an ad for a guy that said 500 for everything
He wouldn’t tell me all that he had
Long story short he had a 30yr collection of mopar stuff everything from complete sets of doors to badges
I don’t remember how much I made but it was in the neighborhood of 10k