Fire rescue radios cannot transmit on the FM radio band used for car radios.
Typo in the termination of employment letter: The letter says to vacate the premises immediately with your personnel possessions. It should have read personal possessions.
There is no Interstate 60 in the US.
The accident would not have resulted in a fatality. The car's airbags did not deploy and the windshield was not broken by the woman hitting it. The woman would have been injured but would have survived.
Skylar was hiding in the garage, and Al somehow knows she is there. He was outside and the door was closed- he had to open it to find her, so he could not have known she was in there to threaten her near the end.
Hadley never follows through after Al attacks- she could have used the tool to kill him in the bedroom, she could have gotten a knife from the kitchen before he attacked Brain and helped Brian in that fight, she could have freed Brian's hands from the piano leg earlier, and she dropped the knife after stabbing Al.
Matthew due to his large size could have easily broken through the bedroom door without any tools.