Hello Steve and welcome to the forum.
I'm sure you will find much in the way of help and good advice from some very experienced window cleaners here, as well as some tips from those who have not been in business long themselves.
although getting lots of support from friends and family, they all say this is the wrong time of year to start ? ok the weather aint to great but surely that makes the windows even dirtier ! whats your experiences ?
Starting in the winter-time or autumn has some distinct advantages. In the warmer months, there tend to be a number of window cleaners that spring up only for a few months. As soon as the weather gets colder, they pack up and do something else, perhaps only returning again the next summer.
This means that if you canvass in the colder weather, not only will you have less competition to worry about, but there will be greater demand too.
Though, having said that, demand for window cleaners has always been good, and is likely to continue that way.
The main thing to remember is to PRICE HIGH. I live not far from you (Bristol) and I can tell you that you should be aiming for a very minimum of £20 per hour with residential work.
There is great temptation to price low to attract customers, that is commonly made mistake. A high price gives an implication of quality, and everyone regrets pricing too low eventually.
Dress smartly, be polite, do not swear in front of customers, do not smoke while working and be clean shaven, and you should have no problem building up a quality round that supports you well, and gives you the freedom of being your own boss.
I hope it works out well for you, and keep us posted here on your progress.
-Philip