Other mistake: Near the beginning of the movie, John's neighbor, Ed, is standing behind a wooden fence that is diagonal across the screen. The fence behind Ed is straighter. The angles of the fences indicate they are too close together - perpendicular sides of fences do not form a "V." Also, two BACK sides of fence are shown. Since Ed is within the fenced area, it is his (not John's) fence and the front ("good") side of the fence should be facing John's yard.
Other mistake: The opening credits show a bit of Ava's rather extravagant biography. She is involved in a DUI accident that kills two people; the news article says that it happened "early Thursday morning." What follows is a police photo labeled 06/27/95, a Saturday. Then we see the police report; not only the incident time is 10:30 PM, but the date is March 15 1999, which was a Monday. It is not separated incidents, since the police photo is then shown again, next to the "Thursday" article (and the fact described in the article is life-changing). (00:08:10)
Other mistake: The weapon which the gunman is holding is a WWII era Nazi MP38/40 submachine gun. The weapon from the magazine housing to the end of the barrel (muzzle) is completely bent down about 25-30°. There's no way the weapon would shoot as straight as it was shooting earlier if at all. I highly doubt the firing pin/bolt can even make contact with the primer of the bullet in the magazine. The weapon looks cartoonish if anything. (00:48:30 - 00:50:00)
Other mistake: Rayburn pulled an arrow out of his chest - and without much blood gushing out. The rather small amount of blood on the towel and Rayburn's ability to go about business as though he had not been injured is unrealistic and absurd. (00:27:00)
Other mistake: When the kid first leaves and enters the house, he takes out the crossbow with an arrow in it but the elastic drawstring is flapping around in front. (00:22:33)
Other mistake: In the montage showing Mike and Marcus' parallel (but also wildly divergent) lives, Marcus asks Alexa to turn down the volume. However, the video he is watching pauses instead. In the next shot, it is paused again, but on a different frame. And before the fan goes haywire and hits the screen, the screen is already turned off (but the breaker hadn't tripped yet). (00:32:00)
Other mistake: The woman was impaled by two stakes, one through her chest and one through her right shin. The man pulled her out of the hole from the edge at an angle to her left side. From this position, he could not have initially kept her body parallel to the ground or subsequently pulled her up at an angle without causing additional injuries or death. (00:14:33 - 00:14:55)