While chasing Paolo and Giannino, police run into another car, initially seen occupied by a driver and a passenger. By the shot at the point of collision, the passenger has disappeared, and in the shot immediately following, the car is empty of riders.
When a man is shot down from the roof and falls down into the cinema, he doesn't land in a position he would if he fell like was shown in previous shot of him falling.
When a police car hits another car during a chase, it seems like the passengers disappeared.
When a man is shot on the roof and falls down into the cinema, it's obviously a doll.
When the main character makes a sharp turn with his car, it's clearly not the actor driving it, but a stuntman. The same stuntman is used in all situations like that.