Do you remember this one?

[erin]

I remember seeing this when I was a kid (around late 80's early 90's).  I want to say the Jud Nelson was in it but no searches are bringing it up. But it was definitely a "B" list actor. It was a horror/comedy about a house that was haunted. A group of bachelors were living in the house or housesitting. There were crazy creatures but the character I remember the most was a green caterpillar that acted like a dog. It's bugging me so bad! Please help if you can! Sorry that the details are so vague.

[Mofo Rising]

You're thinking of House 2.

Some guy and his doltish friend move into a house that for some reason or another contains a portal to multiple dimensions. I don't remember where the caterpillar-dog came from, but it's definitely in the movie. All-in-all, a pretty entertaining '80s comedy.