I went to Crystal Girls once. £60 for half hour / covered BJ. No kissing, got to fondle/kiss breasts, doggie/mish. Perfect for what I wanted. I think anything above and beyond you pay for as "extras", not sure if that would be included in the per hour price which would be £120+
I rang them and had a chat with the nice English lady receptionist, she said that there wasn't any more to pay on the £120 price, but I haven't tested her assertion by actually visiting a girl.
I suppose it could have meant that you don't need to pay more than £120 to actually punt, rather than there aren't any items that the girls won't do unless you pay a bit more.
At these 'extras' places I find that the girls have to hand over a big chunk of the basic fee to the house, but get to keep 100% of the 'extras' money so it's in their interest to hold back services at the advertised rate so they can 'upsell' in the room.
I'd be interested to know what the score is from someone that has visited.