That is why it is best to minimise one's interactions with others and transact one's business online whenever possible.

My opinion is to remain polite but forward (as in stay on the fighting side of nature rather than the flight side of nature without being actually fighting). Ever seen Suits on Netflix? The character of Harvey in initial episodes is never rude but can make big deals in his favor just by smiling. Or seen Saul Goodman in Breaking Bad? (a bit of a scumbag but can't fault him on his charisma). Or DiCaprio's character in Wolf of Wall Street. These guys are never dominating in a gangster sense. But they are big face to face talkers and win deals in their favor.