Mr Solubility. As a window cleaner you often intrude into people's personal space. Those people are usually elderly or women on their own. You go round the back of the house, you see through their windows, you know when they are not at home and where they keep the key to the gate hidden. They feel vunerable
Don't under estimate the value of honest and trustworthy.
Glossy leaflets, give an entirely different message which may work for some but don't write off as dull leaflets which are pitched deliberately at a different target.