The Caprice classic driven by Jack Roth his a 1987 model,
plus , back in 1982, the LAPD was driving Dodge Diplomats, and Ford Limited.
We hear Billy Idol's "Eyes Without A Face" playing in a scene in 1982, The song was not released until 1984.
When Maclaren (Taissa Farmiga) climbs the fire escape with her photographer, she is wearing early 70's "platforms" and "flared bell-bottom" jeans. These were already outdated by late 70's and totally unwearable in 1982, the year this story is set.