Obviously not a current window cleaner, as you can see, but I used to be, and most of my mates are.
In principle, I agree with the guys saying that you get better customers from those who approach you, and you want a compact round not a few houses in each street ... in an ideal world that would be great ... but you've got to start somewhere ... you probably can't afford to spend £000s on a ready round, and if you haven't got any customers, how are you meant to get neighbours popping out to see you? Just park the van in the street and hope for the best?
Canvassing is still the best way to get started ... and, despite making my money from printing leaflets, leaflet drops alone don't work! Call ... speak to them ... even if they're interested, they won't agree to anything there and then because most people are too wary of that these days, but they'll remember you because they've actually spoke to you and you've (hopefully) given them a good quote ... so then leave them a leaflet with all your contact details and the quote in writing and you'll probably have an answering machine full of messages by the time you get home!
Definitely any time after the school run is good ... and not too late so that people don't want to answer the door ... from 4pm till 7pm (or possibly 8pm in the summer months) is my top time for canvassing!