I feel an easy bullseye coming on 
There is know way id sell pure water as its just a easier way for more comp in your area at low low prices and theyve not got to do any homework on how the system works etc just a scrub and a rinse.
Your comments are made sadly lacking the facts.
My "area" is SW london, where around 2 million people live, and some in NW London, with around the same number, so I think the market can stand another entrant!
The reason for my request is simply that my partner would like us to move to an area where it would be extremely difficult logistically, ie a small block of flats! Said flats have a water meter and parking would be an issue!
So, if I can solve the water problem, she would be happy!
I would have thought the nearby areas of Hayes, Acton, and Ealing would have had a supplier, but it seems not at the moment.
taking