Hi, I want to start window cleaning in Guernsey there seems to be a lot of money in it over here as the current window cleaners charge £15 - £40 a house, i got a few questions i'd like to know before i setup

Water - I know some people use hot water from the houses they wash and some just use cold (and some have water boilers in their vans) but what do you do? is there a huge difference between hot and cold water?
Liability insurance - is it worth getting or not? how much do you pay for it?
what % of customers do you get complaints from?
how much business do you lose during the winter months? (if any)
collentions - with the high prices here I don't think many people will have their windows cleaned every week. do you collect monthly for customers who have it done weekly or is it easier just to ask each time you do a house?
Do you have any suggestions on learning how to window clean? I saw in another thread some people take other people on and show them but in Guernsey I really don't think they will be willing to do that
last one

how long did it take for you to get a reasonable amount of customers?