During the outdoor party, the "Goddess of Fire" stands up and walks away from Tony, but in the next shot, as Tony is standing up, she is sitting next to him again.
In most circumstances, a caller must turn his/her radio off when talking to the host of a radio show on air. It causes interference on the radio when the radio is turned on.
At the end of the movie, when Jessie mistakes Misty for the killer and shoots her, you clearly see Misty's character blink two times when she is supposed to be dead.
When Jessie backs away from the door after looking out at the person in the yard, a large strip of gaffer tape is visible on the door frame that was not there previously.
During the opening scene where the killer chases the characters through the woods the shadow of a cameraman with his camera is clearly visible against a well lit tree.