Evening all. I am starting out window cleaning. I understand a little bit of what equipment i need to start up with. I might go for reach and wash pole. To save initial start up costs and to be as competitive as possible with my pricing, could i use ordinary tap water to clean the windows with my brush then use my filtered water to rinse the glass, will this leave any marks still. Will this be any good? Does tap water affect the rubber seals around the glass? my area gives out 40 - 50 pp according to a local window cleaner Cheers x