When Michael goes to answer the door at the beginning of the movie, he is wearing socks. After talking to Beth and shutting the door, his socks have disappeared.
When Michael and Tanya go down the pool slide, they splash into the water twice.
Early in the film, Michael goes downstairs to answer his door. However, a later exterior shot of his house shows it only has one story.
When Charles gets his chest shaved, the same footage of the razor scraping his chest is shown three times.
When Shauna walks in on Michael and Trish having sex, the boom mic is reflected in the mirror behind her.