The things is, I would pay higher prices if I knew the girl provided an excellent service and was stunning. Girls I have spoken to on the issue say "that's what I think I am worth". And that they are not as busy as they want to be. I always say it how it is and that they should look at the competition around them.
It's not rocket science. If there is a girl in Cambridge charging 150 for an hour with limited pics, feedback and details and within a couple of miles a girl who charges 120 with good feedback, plenty of pictures and lots of details then naturally she is the question who is going to get more clients.