You could cover your body in that TCP stuff, and then tell them you are a trainspotter or maybe...
Ok maybe that's not a good idea!
I live in a luxury apartment, I mean a smelly 1st floor flat, when people ring my doorbell I just stick my head out the window and say "Not interested mate!"
In any property you could just stick your head out the window and say "No thanks!" you don't have to deal with them face to face then and they will waste little of your time.
