At the end of the film, Luger and Colt get into a car that has a magnetic police light on the right rear of the roof. As Colt opens his door, it catches the wire from the magnetic light and you can see it turn sideways and begin to slide across the car's roof.
When Colt is mixing his cocktail in his trailer, the bottle of Jack Daniels he picks up is the colour of cola in the first shot but then a much lighter shade when he puts it down in the subsequent shot.
When Colt and Luger surprise Becker in his hotel room, he shoots wildly at them through the closed door, producing a random pattern of holes. A few seconds later when we next see the door, the holes neatly spell out the letters FU.
After Luger arrives at the crime scene for York, a police officer places some tape across the doorway behind him - as he does so, the adhesive pads that stick the fake tape to the door can clearly be seen.