"Act as if you couldn't care less which way they decide and mean it."
People don't care how much you know until they know how much you care.
If you came to my house with that attitude, it would be a very short meeting.
I think he's talking about being perceived as a "salesman just looking for a commission".
After many years, I've seen this "laid back" approach work very well, giving the prospect the impression that I don't need their business, or make the sale to pay the rent. People don't like pushy salesman, and most want to deal with successful agents.
BTW, I'm also interviewing them at the same time, I don't care to take on PITA clients.