(at around 1h 18 mins) At the end, the flashing red light on the police car turns itself off as dawn breaks.
(at around 1h 10 mins) Cop Larry's head wound switches sides several times during the film's climactic showdown.
You can see the truck of the young thugs pass two times in front of the same restaurant.
Hull House is once again the setting. However, the house and the property in this movie do not resemble Hull House from the first two movies at all. This could be a direct influence of Angela, and it is possible that her evil changed the house, and even in the opening of the film it's implied that souls have changed it, and could have been explained easily.
(at around 18 mins) Quicky Mart Clerk never returns the card to Reggie when he gives it to him, but he is seen waving it around in the next shot.
(at around 19 mins) When the cop is hit with the shotgun, he flies back and goes through a window, breaking it. Bullets don't throw people and this was done simply because it looks cool. Classic film trope.
(at around 21 mins) Why is the cop wearing a vest? Police officers typically wear vests through the length of their shifts, regardless of the calls they might go on. This way, they are always prepared for any situation.
After Vince gets his shotgun, throughout the rest of the film, he fires way to many shots out of the shotgun to be realistic, and he never acquired extra ammo, so he should only have what was in his gun, and he shouldn't have anymore ammunition to shoot.
(at around 59 mins) When Lois is attacked by the snake, it's obvious that it was simply a fake skin put over arm with a prop snake at the end of it, and the sounds were dubbed in later. Obvious in HD.
(at around 1 min) The shadow of the camera can be seen on the police officer's car when he pulls into Hull House at the beginning of the movie.
(at around 43 mins) When Angela seduces Orson, a crew member is visible in the picture behind Orson.
(at around 35 mins) It's never explained why Orson points the gun at the others.
(at around 1h 16 mins) Towards the end, the cop tells Nick and Holly they were not caught on the surveillance cameras at the Quick Mart, so they could just go on home. However, this is highly illogical, given the fact that Nick and Holly are seen walking all around the inside and outside of the Mart, just like the other characters are. If the others have been seen, it wouldn't make sense that Nick and Holly weren't.