Thanks for the article jeffrey!
My
mother in law is too shy to negotiate procies with vendors.
She has a simple rule, visit as many stores as possible and ask “what is the price”. Ask ask ask

Once she gets to the final vendor, she simply sais: “I saw it in a store of a friend of your for the price of X. can you give it to me in the same price?”
That’s it! Usually she gets what she wants just by the power of asking!
David