Continuity mistake: This film is based on the Rettendon Range Rover Murders in 1995, when some drug dealers were killed in a Range Rover, however in the film a new (1995-) Range Rover is used, I believe from footage at the time, a Range Rover Classic (1970-1995) was the car they were killed in.
Continuity mistake: The Bentley was set on fire at the beginning of the film at the car dealership, then it reappears at the end of the film outside Peter Chase's house.
Factual error: The scene at the very end of the film where Billy is grassed up by Alex Kingston. I live in Essex so know that you cannot see Ye Old Plough House (the motel) from Southend Sea Front (the phone box).