The interviewing process consists of two interviews. The fist was with the VP of sales and consisted of a variety of questions, its important that you have well though out questions as well. If you are asked to move forward with the interviewing you most likely will be meeting with 2 sales managers and you will be asked to go on a ride along to see what the job is really like and if it's something you can see yourself doing.
Second Interview: Be prepared to make a good sales pitch, this will be based on material they give you.
The ride along: make sure you take full advantage of this part of the interviewing process, you might be going into shops with the intention of getting an appointment. (Work hard here)