When Jade and Cooper drive from the house, the surroundings of the street change in the different cuts. In particular, when Cooper leans forward to pick up the key from the floor, one cut shows houses along the street on both sides forward, and the next cut shows open land and a wall (when the man with the rifle attempts to shoot Cooper).
When Cooper is winning jackpots inside the casino, he only inserts one quarter in the machines. However, three quarters are required to win jackpots in the machines he is playing.
When Jade drops off Dougie (Dale) in her yellow car at the casino, Dougie/Dale attempts to enter through the revolving door. In the glass reflection of the right window, Jade's yellow open-top car returns to the car park entrance. This isn't a mistake and is clearly visible intentionally; Jade was dropping Dougie off because she was going to the same place.