Will this be your only experience at bookkeeping? I am a freelance bookkeeper but i would not go straight into self employment without first getting some experience in the 'big wide world'. I worked for the Inland revenue for several years so i had some understanding of it. Then i worked for an accountant, absolutely rubbish pay, but i learnt a lot. I have worked self employed for builders ( you need an understanding of the CIS scheme), a doctor, milkman, software company, a pub, optician and did more freelance work for an accountant. They all had different methods of bookkeeping ie computer, manual, which includes different VAT schemes.
If you are a seasoned bookkeeper, please ignore my comments you will already know this.
If this is your first attempt, i would seriously consider going out in the field before taking it on all on your own. Not all (well very few) company's run text book style.
Where i live self employed bookkeepers ask anything between �10-�15 ph. some ask for mileage exps too!