If you visit the homepage, there's a "Get Started" button. The next page is a form asking for your trip details. Once you complete the form and pay the finder's fee, experts start competing to build you the best itinerary. You can communicate with the experts during the process to specify preferences. Clearly it works best with higher-value itineraries.

A more high level explanation is that Flightfox is a marketplace for freelance travel agents (and flight experts). We're bringing human travel experts online with a new crowdsourced model. Because customers pay a fixed fee upfront, we hope to remove the dependence on commissions. With diminishing commissions on flights, it's difficult to find agents who'll take the time to find you the best flights. That's what we're aiming to fix.

For frequent flyers like yourself, we're currently building out features to also earn/spend miles. I'm not sure if you do mileage runs or book award flights, but this is where we could become much more interesting for you.