There are lots of different variables i.e where you are in the UK, the type of client, how much do you usally charge and your time! I am based in slap bang in Central London with lots of wealthy clients who pay between £12 and £20 for regular cleaning without batting an eyelid. I done a Spring clean yesterday on a 4 bedroom house the house was very clean but the client was very difficult and wanted blood it ended up taken 7 hours instead and I could not charge more as price was already agreed, you just have to use your judgement but alsways allow more time than you think you will need, not double but if it is a 2 hour job give 2.5 hours to do it properly and charge accordingly I hope this helps a little?