I don't know - I'd assume that depends on the situation - do they know you're there/how do you know not to answer the door?
Do you just never answer your door, never make yourself visible from any windows etc..?
I guess if you live in a flat and/or have a video entry phone then you could maybe sneak a look at the camera first and perhaps if you're a floor or two up they might not be able to ascertain which flat is yours etc..
this is the rub for me, if you do not converse in anyway with these men/women who come to your property then what? you say their policy is to not force entry, it's a bit of a standoff/stalemate situation.