We only have a very limited scope as to which to judge this since prostitution is legal in only in some counties in Nevada, and the licensing of such is not standardized from county to county. Assuming its in one of these few places, the standards would be set by the county licensing agency. Otherwise, there doesn't need to be standards because, like someone already mentioned, illegal prostitiution is individual contracts negotiated at the time of engagement and hazard is factored in as part of supply costs.