It's the topic of many review boards, hobbyists and sex work enthusiasts alike, often remarking on the prices of services and what they think the associated values ought to be. Many of whom, do not take into account the various financial costs of operating a successful business, as well as the related time costs of being an attractive woman. Here by no means in an exhaustive list of what you're really paying for...
1) Time: first and foremost, you're paying for the time of that provider. Whatever happens during that time is irrelevant, it's their presence that matters.
2) Risk: you're paying for not only the providers presence but the risk that is associated with that. Risk can be physical- as providers are at a much higher rate to be victimized, it can be social- as working in the sex industry is stigmatized, it can be legal- as many places carry legal penalties for sex work. Where there is risk, there is cost.
3) Product: our bodies are the product for which we provide services. There are standards and expectations that providers try to meet. These include beauty costs (hair, nails, lashes, tan, makeup etc), wellness costs (fitness, skin care etc), attire (lingerie, clothing, shoes etc) and medical aesthetics (Botox, enhancements, fat reduction etc).
4) Administrative: many of us have websites, advertise, have professional photos taken, use booking sites and other services that we require to run our businesses.
5) Equipment: our in call location, our phone, lap top, kink gear, condoms, lubricant, sex toys etc.
6) Transportation: out calls require transport, if you don't live at the in call you use then you also need transport, to get to the dungeon or the massage parlour you need transportation. Then there's the touring: flights, cabs, Ubers, trains etc.
Like I said, this is not an exhaustive list but merely an example of what the associated costs of being a provider can be and some insight into how we price.
Here is an overview of what I spend to run my business successfully, both time and money because time IS money!