You know what I did when she asked for a $60 tip for a BBJ? After I said a polite, definite "no"? I let my dick go soft. I looked her in the eye, focused on something else, and let the blood drain away.
I was at an AMP where I know the girls generally aren't comfortable with failure. Deflation was a message.
What happened? After she lowered the ask to $50 and got zero in response from me, she put my dick in her mouth uncovered. That BBJ didn't cost me a penny. The shame of it was she was hot.
Good strategy.