Rent-a-Girl is a short (77 min) sexploitation flick with all the elements you would expect: topless girls (who often aren't that good looking), a little kinkiness, extremely bad music, poor acting, poorer editing, and unintentionally hilarious dialog.
The heroine in this case is fairly pretty, but we don't actually see a lot of her; other "rented" girls go thru their set pieces more graphically. The plot revolves around our heroine's distress about falling in with a cheesecake modeling agency that turns out to be a call-girl ring--except that the girls apparently don't actually have sex with clients; they just disrobe and play around a little.
A bit of decent acting here and there stands out, and the plot moves along in workmanlike fashion, but there are no real surprises. Yet, as with sexploitation in general, there's something weirdly erotic (to some of us, anyway) about seeing vintage skin, tame as it is--it's the alternating brazenness and shame the characters exhibit, contrasted with the strict innocence of mainstream films of the era. This is a decent effort, but not a classic.