Having engaged a proper commercial window cleaner for the last ten years or so, I can honestly say it’s boon. Trying to clean the upstairs windows without this hep is now getting to be anightmare. It is possible of course, because modern windows are designed to be cleaned from the inside and I could do it if neessary. It involves openeing both side windows to their maximum and leaning out to clean half the centre pane – from each end of the window sill . . . . . The other method is to have tilting ones that can be unlatched and turned almost ‘inside out’ and the external side cleaned in the vertical position. When I have tackled them, I’ve found a clear spray cleaner with two eco cloths work best – I manage a much less streaky finish by spraying and wiping vigorously with first cloth and polishing off with the next. Shaking the cloth and using fresh patches each time also helps!