Several years ago I was at a Jim Ryerson salesOctane sales training session as part of an Entrepreneurs’ Organization workshop. After covering a good bit of material we were in a section of the program on sales questions and prospect conversations. There, I learned one of the best sales questions ever that still sticks with me today:
How so?
It’s so simple, right? Salespeople have two ears and one mouth for a reason — listening should be done twice as much as talking. When asking questions, it’s best to ask open-ended questions as opposed to yes/no questions. One of the simplest and best ways to get a prospect to continue talking is to say “how so?”
Tomorrow, when talking to a friend or family member, try using the “how so” question and see how well it works to get them to continue talking and sharing information with you.
What else? What are some of your favorite sales questions?
David Cummings on Startups 
I worked in a restaurant for quite long time and I was a great up seller
My favourite questions were:
What wine would you like with your main?
What salad would you like with it?
What coffee would you like with your cake?
I was also nodding ( Sullivan Nod) while asking those questions.
great advice, I’m going to try it with my clients.
Definitely a very effective phrase when you want someone to open up. I’m also a fan of the ‘pregnant pause’ on calls and demos, silence makes many people uncomfortable and often they’ll offer up new info to fill the void.