one word sums up this entire post...
LAZINESS!
People can't be bothered cleaning their own windows, nor can they be bothered picking up the phone. Instead they wait until you call at their door and then they hire you.
When I started my latest round back in 1998, I put out 14,000 leaflets. How many calls did I get? 30!
But when I went ot clean the windows in a street, I would get 10 more gfor each person who called. Some I even asked, "Didn't you get my leaflet?". "Oh yes, dear. But I thought I would just see you"
Needless to say, I didn't waste any more cash on leaflets!
Best thing is top get your van properly signwritten. Got more work through that than anything else.