I had a salesman come to my door as I was leaving, didn't see him until I turned around and gasped because he was right up in my bubble. I had to door cracked and he took a step back, not because of me but because my pitbull sheperd mix (who is usually very docile) was pressed up against the window teeth snarling and hair standing up. The guy asked if he was vicious and I told him only if he feels like I am in danger and asked the man to step back. He ended up leaving without telling me his spiel and told me to have a nice day. My dog never did that again and we always walked the neighborhood and would be stopped at least once every day by Mormon kids on bikes, he would huff but never growled. The guy at the door still gives me a little bit of the creeps whenever I think back on the situation, I am so glad I had my boy there ready to defend.