solution=DON'T answer the door!
But what you did was without a doubt pretty funny. There have been a few times in which they've caught me off guard and I've answered the door thinking that it was someone else that I was expecting. They can be VERY pushy and persistant. Sometimes you just have to slam the door in thier face in order for them to leave you alone.
It's also a plus to have a BIG threatening looking dog right next to them, growling. And when they ask if bites or not, say, "only if I tell him to..." That'll scare the shit out of them, and they won't come back for long time!
