The Fool is exploring Seattle. Today, CEO Spencer Rascoff introduces us to Zillow, telling us how the online home and real estate marketplace works, what he considers its greatest strengths, and what investors should know about it.

What don't investors see? Spencer explains that Zillow currently holds a tiny fraction of a massive addressable market spanning four categories, and he talks about how the company's consumer focus will allow it to do right by its stockholders.

See more in the following video. A transcript follow.s

Austin Smith: Obviously there's a lot of things going on, so a lot of different revenue streams, a lot of potential revenue streams in the future. What's one thing, given all that, that you think investors commonly miss with you guys?

Spencer Rascoff: I think investors sometimes get our total addressable market wrong. There's a long history of publicly traded real estate companies that have crashed and burned. That sometimes sits in the back of investors' minds.

The reason why most of those other companies have crashed and burned is they haven't focused on the consumer. They've focused on the professional.

Our north star is the consumer. We worship her, the home shopper. If we do right by her, then we'll do right by professionals, and then we'll do right by employees, then we'll do right by stockholders. What investors, I think, get wrong is misinterpreting the past in this category and misevaluating the size of our addressable market.

In the four categories that we're in -- real estate, rentals, mortgages, and home improvement -- professionals spend $35 billion each year in the U.S. advertising their services to those types of consumers, looking for those four services.

Smith: That's collective, all four.

Rascoff: Collectively, $35 billion. We're a tiny, tiny, tiny, less than 1% fraction of that $35 billion addressable market.

Smith: I think we posed the question earlier, but I'd love to hear your take on it as well. Zillow Digs -- a great product -- I use it myself, it's a lot of fun. It seems like there's an obvious monetization track here as lead-gen for contractors.

Rascoff: That may be how we choose to monetize. Candidly, we haven't discussed it much yet. The focus for Zillow Digs is growing audience. Right now, this product is six weeks, eight weeks old. We need to get to a place where 10 million, 20 million people are using it every month to plan remodeling projects.

Then there are a lot of ways to monetize at that point, whether it's local lead generation or display advertising or integrated e-commerce where you're buying some of the things that you see there; we'll figure all that out down the road. Right now, the product development team at Digs is focused on growing audience.