Narm: During the gang rape, one of the attackers is wearing a rather stupid looking polka dot hat.
Narm Charm: The conversation between the killer and Red (one of the construction workers killed in the house).
Shocking Swerve: Everything pointed to Linda being the villain, from dialogue to the fact that the killer was was obviously played by a woman. Then it turns out it was Bubba.
Special Effects Failure: When a victim falls dead onto his grill, you can clearly see him stick his hands out to steady it and stop it from falling forward. The nail gun is also never shown directly firing, nor are the nails (which are prone to wiggling) shown entering flesh.
What an Idiot: The two construction workers play fighting with loaded nail guns.