haggle
When you try to talk someone into giving you a better deal by throwing insults and fake tears at them until they cave.
'I'll take it for $10 or I'll scream your mom's name in the middle of the mall.'
'You think I'm stupid? I'll haggle you down to $5 or I'll tell your boss you're a crybaby.'
'I'm not paying $20 for this bag of chips. I'll haggle you down or I'll make you eat it in front of your friends.'