Do you know of any holiday rentals in the UK that allow under 18's and single groups?

We are a group of girls- 11 of us. We want to go away for a week in August preferably, but we are all going to be 17 at this point. We want to stay somewhere in the UK, weve looked at Bath, Bude in Cornwall, Devon etc. We want somewhere preferably around here. Also, we need it to be within walking or bus distance of activies like shops and nightlife. Do you know of anywhere we can stay or rent out? No caravans please, and serious answers :)