In the episode iStage an Intervention there's a slip up in the door to Carly's apartment. When Freddie comes over to get the tennis racket you can hear the door slam, persumably closed. When the camera pans out you can see the door is open and swinging, as if it had just slammed against the wall. It continues to be open as the kids are talking. However, when the Spencer starts talking about his score on PacRat the door to the apartment is closed. When the scene goes back to just the kids Freddie walks out of an already open door.