When Billie Jean delivers alcohol to Barney's woman, she knocks at a door with two panes of glass. When she enters the house, the door has one pane of glass.
As Charles takes the money during the bank robbery, the squib pack on his lower back is visible.
At the racetrack about 43 minutes into the movie, there is a 20 oz. coca-cola bottle on the railing. The movie is supposed to take place in the early 40's.