Visible crew/equipment: The first time Candy enters the house, John waves to the guy across the street. Whilst he's doing this, you can see a reflection of the crew in the front door window.
Continuity mistake: When Johns parents come home early, there is a shot outside showing his parents set off down the path to the front door, then there are shots inside of everyone rushing to clear up before they get in. Then it goes back to an outside shot of his parents coming down the path, but they should have reached the front door already judging from the time of the shots inside.
