lost a house to a trad guy becasue he will go up a ladder and wipe the sills, cant see it working out too well my self its three stories high :-)
This is in direct contradiction to anything i've experienced. What i can't understand though is how are you not wiping sills? Or you are and its not good enough? Whats the full storey [pardon the pun]?
Its the brush angle that's important at this height if you haven't a sill brush. Usually the brush head at the right angle to clean the sills is too acute to work comfortably on the windows, especially across the top.
The answer is to clean the windows as normal, then collapse the pole, change the brush head angle and put it up again to clean the cills. Doesn't take long, but usually too much trouble to do it.
We have found the splayed brushes help a little in this regard and are a better compromise, but not as ideal as a cill brush.