After Gary becomes ensnared in the electrical conduit, as he is rolling on the ground and Sheila is pleading for his release, you can see the end of the conduit becoming unraveled a bit early.
Twice during the course of the movie the house activates its solar panels and begins to heat the pool water in one scene and the furnace in another. Unfortunately, this wouldn't be possible as both scenes occur at night.
Gary and his nurse Shelia break out of the house. Right before the hose entangles Gary, the gate slams shut, and the wheels aren't lined up, but in other shots they are.