At the beginning of the movie, Stephanie is tapping a purple pen on her notebook when the ceiling leaks and a close-up of her hand is shown to let us see the water. In the close-up she has a pink pen, then it cuts back to her holding the purple pen. This was fixed on the DVD but it remains on the VHS version of the movie.
During and after the scene when Knowles calls Lester from the pay phone it is snowing outside. However, between the call ending and Lester taking the guard to the roof, there is a cutaway shot of a helicopter and two snipers and there is no sign of any snow.