in London I use agencies almost exclusively as they are not rip off merchants like over here. I've always been surprised that someone hasn't tried to give it an honest go over here.
I've done so on many occasions, but Irish pimps can't handle the competition, so they email Garda or the newspapers telling them what's goinng on; I;ve had both the Garda and the newspaper telll me in a two week span they got emails about me running a brothel.