The Guerrilla wants to find out what the client heard him say on the phone when he got the appointment, not what the guerrilla thinks was said or understood. So, he ask something like, "So I can be more effective with your time, will you please tell me what you heard me say that made you want to see me today?" This may appear a bit long and somewhat convoluted, but it is a very powerful first question. It will get you big results. Memorize it and use it today.