I have had my wfp set up for nearly 3 weeks now, do what I did windy, clean your own windows and some of your family members houses (free) untill you get used to it mate, if your windows when dry dont look any good after they dry , then stay trad with your custies windows, untill you get it right! ...... practiceing on your own windows . Thats what I did now all my windows I clean wfp are 110% and custies stay happy....Barry.