At least Amityville II: The Possession has some basis in fact. This is -- on the surface -- the story of how the DeFeo family (here the Montellis) got murdered one night at 112 Ocean Avenue on Long Island, New York. (The subsequent events are the subject of the original Amityville Horror.)
In real life, the eldest son of the DeFeo family murdered six of his family members in their sleep while they slumbered in their beds. In Amityville II, the family structure is about the same -- and they all get the business -- but little else remains intact. Here we have a tale about a rough and tumble kid named Sonny (Jack Magner), who hates his father, romances his sister (Diane Franklin, best known as Better Off Dead's Monique), and gets possessed by demons who live in a secret room in the basement.
Continue reading: Amityville II: The Possession Review