Weird thing that drives me nuts
I'm from St. Joe, MO, so well versed in Jesse James lore...
But the house they chose is a damned near mansion compared to the real thing. The real house is crazy small...4 rooms...all the same size - maybe 10 by 10, little cube house...and the movie house is just massive and two stories: I realize it's a weird thing to go nutso about...but seriously -- easy to recreate it.
Most interesting aspect to the house, aside from it's tiny size, is that the bullet hole that was left in the wall after the shooting was carved to about the size of a baseball. Men who went to the house scraped off bits of the bullet hole with their pocket knives and the hole grew in size. They put glass over it to stop it, but the bullet hole is insanely big, and that's why.