I've always found if you are cheerfull and chatty, you get more work and you tend to keep it.
By chatty, I don't mean you rabble on for ages but you take note of or sense when the customer wants to talk or when they don't want to or you know when enough talk is enough.
A very good few months back an elderly neighbour of one of my customers was unloading bags of shopping from her car so I said I'll carry them for you, etc, etc, etc.
Last month, she asked me, via the neighbour whose windows I already clean, to clean her windows having got rid of her window cleaner.
Yeah, a smile and a bit of proper human interaction gets you work but not always straight away.