Surely all people want is for their windows to be clean
Totally wrong in my experience. If that was true, then customers would choose solely on price alone, and they clearly do not (which is good because I'd be out of business if they did)
If you say you're a window cleaner, they expect you to clean the windows, thats taken for granted. What they are prepared to pay for, however, is the polish of the professional.
That could be something simple like wearing shoe covers if you go inside the house or a uniform or wearing a photo ID badge with info they can check up if need be.
Or it can be (esp when going for contracts) making sure they understand that you've invested heabily in the proper equipment and are not a bodge-it man.
The window cleaners I know that have bodged together systems dont manage to get anywhere like the prices I can get, because they dont act professional.
Do they clean the windows as well as me? Of course they do! a clean window is a clean window! Customers arent paying my extra for that, they are paying more for me being a pro with a pro attitude.
Some people will never get their head around this and just dont see the value of investing in your image. Thats great, I'm glad about it because it makes me stand out above them. A pro attitude cant be learned or taught, you've either got it or you havent. And IMO if you think "I'm not paying to have my van properly done, bcos its only window cleaning" then you dont have it and never will. Bad luck for you.
Mike