The reason that the Ghoulies were played by actors in costumes as opposed to puppets was because Cinetel Films couldn't afford to use the puppet props of the original Ghoulies.
Re-uses the same haunted car chase sequence from 976-EVIL II (1991)
Stacie Randall has gone on to say that she is embarrassed by her involvement with this movie.
Ace Mask plays a character called Doctor Rochelle. He also played a character called Doctor Rochelle in both Not of this Earth (1988) and The Return of Swamp Thing (1989). All three movies were directed by Jim Wynorski.
A fifth Ghoulies movie was planned but never materialized.