The £9 per hour outfits are usually agencies, a lot of whom use self-employed staff, so after the staff have been paid (often by the client) the agency fee -usually paid by DD or standing order from the client to the agency- is the agencie's money.
To be honest though, the fact that people are running cleaning services with materials, staff, and insurances all in one, and are charging hourly rates (of however much) and not agreed 'quoted' prices, seems odd to me, as round my way those who work like you do will not give a price over the phone, they will want to come and see the job and charge for doing it, not for the time taken.