Night changes to broad daylight, then back to nighttime again in the opening scenes.
An old man can clearly been seen standing and watching the filming crew, as the last girl walks up to the building.
In nearly every scene filmed in the kitchen, a crew member can be seen holding a small hand held camera, reflected in the kitchen windows.
As the last girl walks up to the front door and talks to the bald guy, the boom mic and its wires are clearly visible for several seconds.