When Shawn arrives at the night club following his first fight, he steps out of the car clearly sporting two bruises on his face. After the scene shifts to the interior, his bruises have all disappeared.
The cardboard box full of umbrellas that Shawn carries varies from soggy and falling apart to dry and firm almost randomly during one scene.
In the last fight, Evan takes off his warm up jacket twice.
At about seven minute in, Shawn MacArthur crosses the road under heavy rain with a wet box. A minute later, after he gets his money back from Harvey Boarden, he's back on street where there is no water, no rain, and his box is fully dry.
When Shawn tells Zulay he wants to help her with her rent, strands of her hair move on and off her face between shots.
When Harvey pays a visit to Jack's office in the back of the store, Harvey knocks on the door then proceeds to enter the room. In the next shot, one of Jack's men opens a second door for Harvey and there is a wall and a clothes rack behind Harvey.
The bundles of cash used in the movie are badly made props. They were printed with black ink on thick white papers.
In the last fight of the film, Shawn rams Evan into a wall, which caves in from the impact. When Evan pushes back, Shawn reaches out for something to grab and accidentally pulls down the "crumbled" section of wall (actually a thin sheet that had been placed over the real one), exposing it as a special effects prop.
When Shawn comes out of the cafe, the tour bus makes a right turn. When the scene angle changes and goes back, the bus is nowhere in the scene.
In the scene where Shawn goes into the diner to get his money back from Harvey, the boom mic is visible at the top of the screen.