Help Finding Retro Porn Title

[greencasey]

Its been almost 20 years since I've seen this so my memory is a bit fuzzy. I remember it was in English so I know it wasn't foreign.
I'm thinking it was made sometime in the 80s or late 70s but I really think it was in the 80s.
I remember it was about this mansion or huge house where a lot of sex was going on lol. The star of the film is a guy, who I think goes to live there--I think that's the main story of the porn.
I specifically remember a threesome with another guy and two girls in a bedroom. I believe he was the repair man or cable guy.

The two girls sort of end up forcing him to have sex, one girl on his face and the other riding him. And one thing I remember, is him having a birthmark on his butt cheek--this medium sized spot on his ass lol.
Another scene that I remember vaguely, is this lineup of all these different guys being sucked off in the living area, which the male star of the film witnesses when he moves into the house in the beginning of the movie.

Any help is appreciated if you were able to get an idea of what I'm referring to. Thanks in advance!