His brothers wife (his brother died from syphilis shortly after him) ended up with all his work and believed in it too. She was able to impress other with it and held a large show featuring his work a few years after his death and this is how he came into prominence.
I was talking to a friend of mine who is a reasonably famous and financially successful modern impressionist painter about the market selling his oil paintings. It’s more than just the right contacts, the entire thing sounds more awful than used car sales, honestly. Lots of game playing, politics, back stabbing, and scamming. Just asking him what I figured would be a straightforward question of what kind of percentage commission galleries charge led to about on hour long conversation that I could barely follow.
The short version seemed to be that if you’re naive or trusting, you’re screwed.