Ron
If you tell the customer an hourly rate he/she will think its not good value, for example. a 4 bed house with 2 bathrooms etc, if you tell them it will take 2 people 2 hours (4hrs)and the rate will be £11/12 per hour plus vat, they will imediatly think of Mrs mop round the corner who will charge £8 cash in hand. our price £44 + vat or £32 for Mrs mop?
My advise would be charge per job, sell the benefits of what you can do, and how you will clean it, what system etc. then hit them with the price, they will somtimes pull you up and ask you how much per hour it works out at, keep to your guns and tell them you charge per job. in my oppinion you need to be looking at charging arround £12 to £15 per hour.
Kind regards Phil