This is not a shouting match, but it could get that way any moment now.

"I'm not impugning your quality, Mr. Ollivander, but if you don't want to sell me a wand -"

"I have sold you a wand, Miss Swan, and if you say it does not suffice for your purposes I do not see how else I could possibly interpret you."

"Only in quantity!" she says. "I just want two."

"With an attitude like that you might one day find yourself in possession of two pieces -"

"That's exactly the sort of reason I want a second! If you won't sell me one -"

"I have sold you one, good day, Miss Swan!" Ollivander turns to the next customer. "Pardon her. What can I do for you today?"