As mentioned previously Sheffield Belles is an option, £70 for half an hour.
Pretty much as Ali says. The girls are usually nice enough, rarely amazing. The rooms are pretty basic actually.
They do have a private waiting room - I think you just walk in and turn left, but I've never used it myself. The first time I went to one of these places it did put me off but nowadays it really feels like any other waiting room.
On the whole I've been in pretty much the same boat as you. There used to be more indis & more options where I used to live - and actually cheaper. GFE is approx the same price as an indi (for HH anyway) and I've had a lot more independents disappoint. You get the option to see the girl beforehand, you know you pretty much aren't going to be left sitting in the street with your phone - became my lazy automatic choice.