With all due respect I've been canvassing for window cleaners for years and although you do get cancellations, the extra 10% we give covers the fallout, it depends how canvassing is done, if you get people that will just sign up anyone they can convince then yeah, you're gonna lose loads. We, however only sign up those people that actually want a regular service and the phrase "ahhh yes please we've been meaning to arrange this" from successful people who own detached houses is something I hear every day.