In the phone interview, they ask many sales-based questions like name a time when you gave exceptional customer service, name a time when you dealt with a difficult customer, name a time when you convinced someone to do something they didn't want to do, name a time when you motivated others, a time when you successfully made sales.
At the headquarters interview the questions included: what is the accomplishment that makes you the most proud, successfully made sales, motivated others, taken a leadership role -- very similar to questions asked during the phone interview but a little more in depth.
Here, they are definitely looking for people who want to work there long-term. When they ask if you have any questions for them, be sure to think long term.
To give you a rundown on numbers: 400 people were interviewed on the phone, 40 were chosen to come to headquarters, and 10 were offered the intern position.