At the moment, it's the old rules: Sex for money is legal; doing it publicly, or arranging to do it are not. Doing it privately is OK, but operating the palce where such things are commonly done is not (nor is just being in such a place if they scoop you) and similarly just about any other service sold to assist prostitutes is also illegal.
But police have very few zero-tolerance policies; they're difficult to maintain, of dubious value and distort the real purpose of policing: an orderly, if not necessarily 100% law-abidin society. So given operators and practitioners who exercise common-sense discretion about their fringe occupations—what Queen Victoria used to call thoughtful enough 'to refrain from doing it in th road where it might frighten the horses'—the police will tend to leave well enough alone. They'd rather the places they know about did the business than constantly having to detect the new ones. They just have to watch their buds on the Drug Squads to see how stupid that game is.