I had a phone call this morning from an 'ex' customer wanting me to clean her windows. When I took her on I had to twist her arm to get her to agree to a regular clean, since she wanted an 'on demand' service, but I won't do that so we agreed £100 charge for a clean every-three-months inside and out (it's part of a large manor house and a bugger to do; a tough two-hour job for two of us; and she did think we were expensive) and some time last year when I phoned her the night prior to her clean and left a message, I received a message back saying 'no thank you, they don't need doing!'
I was a bit cross about this, since she broke the terms and conditions we originally agreed; but I just let it lie.
Anyway, this morning she phoned me wanting to clean her windows and she tried to 'butter me up' saying we did such a good job last time they didn't need doing for ages! She also said she hadn't had another window cleaner.

I reminded her of our original terms and conditions, and politely told her 'no'.
The thing is, it's a bugger of a job. You wouldn't want to do all those extremely high Georgian windows from a ladder and you can't use a van mount without running the hose through the manor house; not all over that cream carpet she's got (it's a proper 17th Century manor house; it's massive and has immaculate lawns and gardens either side that you couldn't drive a van on; you'd need a 500 meter hose), but perfect for a back pack where you can carry your water through the house.
I think she should've stuck with the devil she knew, since she's going to struggle to get a reliable window cleaner without paying over-the-odds. I suspect she found a cheaper window cleaner whose since disapeared, and I was also given this job from another window cleaner who didn't want it; she must realise that even though it's a big job, it's not a 'wanted job' for any window cleaner!
Some customers, no matter what their income levels, suffer from a lack of common sense. Don't let them take the mick.