I price mine up by how long it will take me to do one job. Because am a new window cleaner am a bit slow with the WFP but ive only worked with it for 2 days... and on my 2nd day i felt much better then the first day ! I charge a customer £8.00 for his house.. with a conservatory and that should take me 20 minutes to do once i pick up my speed I also charge another customer £10.00 for the same type of house but with a few extra windows, this should take me 25-30 minutes to clean once i pick up my speed Then ive got a few houses that i charge 5,6 pound for.... which will take me about 15-20 minutes to clean. And i got a few houses that i just do the front for 4-5 pound and this should take me only about 10 minutes ! I like to price my jobs up by how long it is going to take me instead of how many windows.