My first private treaty, and a mini-completion: Cents of 1839
I've always thought the phrase "private treaty" sounded way too fancy, but if the shoe fits . . .
In my case, I was fortunate to work out a deal for an 1839 head of '38 large cent with a gracious member who posts here as "coinnut". As I posted recently, I'm working on an 1839 mint set with varieties that is likely impossible to complete due to a certain half dollar. But at least I've managed to get all five major cent varieties from this interesting transition year: https://www.pcgs.com/setregistry/mysetregistry/album/showcase/6612 .