A young man gets a job as a door-to-door salesman and tries to fight off advances from the female customers.
A provincial lobster fisherman (Brendan Price) decides to come to London for some reason and winds up in a boardinghouse full of luscious lovelies. One of them (Sue Longhurst) is an "actress" who gets him a job with her on a "blue movie" where she proceeds to shag the holy hell out of him for the British version--and then they do the "continental version"! Another of the girls, "Sally Cockburn", comes home to find him occupying her old room and bed, so even though they've never met, she proceeds to strip off and hop into bed with him. Felicity Devonshire meanwhile plays the youngest of the girls, a "17-year-old" who would no doubt succeed in teasing him to death, constantly flouncing around seriously under-dressed and begging him "to make her a woman", if he weren't getting so much sexual release from her "older" housemates.
There's also a repressed religious girl and a nice Jewish girl who gets him a job as a door-to-door salesman at the vacuum-cleaner company where she works, which finally justifies the title. Of course, this also gives him an opportunity to have even MORE sex with various randy housewives. This whole time though he has fallen in love with a French au pair (Jean Harrison), who he first picks up on the highway wrapped only in a towel after one of HER romantic escapades has gone awry, and he tries to convince her to stay in England.
One sure cheating wife scene is at 1:05:08. Our main guy has to escape out of the window when the wife's husband suddenly arrives while the two of them are in bed.