At the table read, Lohan had a script, where in large writing it had Nolan Gerard Funk's name crossed out with the word "NO!" next to it and other casting suggestions. But by the end of the table read she had changed her mind and at the next rehearsal was thrilled to be working with him.
When Ryan comes upon Cynthia stabbed to death in her apartment, the camera does a slow close-up pan across her "corpse" in which the actress's pulse is clearly visible in her neck.
When Tara and Christian are by the pool, in some scenes we can see direct sunlight shining on Christian's face and Tara's hair and back, but when the scene changes to another angle there's no direct sunlight at all.
In the first scene Ryan asks how long Christian and Tara have been seeing each other, the answer given by Gina is a year but when Ryan comes clean to Gina later in the movie he says he and Tara broke up three years ago when she started seeing Cristian.