Welcome aboard Peter. I am new myself and officially go self employed on Monday (im shelling bricks!) just to comment on...
I have bought the ladders etcetera and very excited to have a go but I do not wish to upset any local window cleaners
Look, the golden rule is that you must ask the potential customer if they already have a window cleaner. If they say yes just move on, if they try to drag you back tell them that you are not going to take someone elses business off them, go to the house right next door (not the next street).
If you meet any other cleaners then tell them your situation, you can tell them straight that you always ask if they have a window cleaner and if they do you do not quote as you are not taking anyones business away from them. They may even offer to give you some of the work they no longer want for free.
and finally...
Wow! what can I say lads, those offers to help this guy out just bowl me over. You kinda know your in the right place when stuff likes this happen.
PS Get a ladder M8rix, ladder mitts and some rope too if your doing traditional.