Whatever way you do your "door kill" you will be letting competition in, do you think that if you drop someone they are just not going to bother getting their windows cleaned ever again?
No, they'll find someone else to do them, they may even be cheaper, better, more reliable....... your ex customer will tell their neighbours and their friends in the next street about their new window cleaner and before you know it there will be a new window cleaner on "your patch" and you've suddenly got competition.
What do you do

If you really want to downsize, then find someone to buy it off you, at least that way you'll get something back from it.
Otherwise, and in my opinion the only option, keep it and replace the person you've lost.
How do I know this, because there has been many times over the last few years that I have done this to others, gone into a street with one phonecall from a potential new customer who has been let down by her window cleaner and we have ended up taking most of the street/area.
If you have 2000 customers a month that is a BIG concern, even if they are just 2 up 2 downs, don't throw it away otherwise someone like me will come along and take it all off you
