They will employ every high-pressure tactic in the book and then some that are considered crimes against Humanity and in more civilized societies are punishable by death. You will be able to observe a sequence of increasingly confrontational salespeople, male and female, pretty and ugly, that seem hell-bent on selling you some nice time-share in a chain of resorts. You will also see others succumb and be applauded for making a really stupid business decision.
I advise you to do it as many times as it takes for you to master the game. You may consider yourself ready when you consistently beat up the final boss and get your prize (usually tickets for some tourist attraction). I particularly like to play rude paying more attention to the food than to the salesperson, interrupting and leaving the table to get more food.
Do it a couple times a year, just for the kick of it.
It's like an immersive videogame.
OTOH, your faith on Humanity may end up a bit scratched. That's a small price to pay for this kind of enlightenment.