Marking its 20th anniversary, the expo provides a window into the little-discussed and low-cost backbone of the art market. The Affordable Art Fair does things a little differently from its more prestigious brethren like Art Basel and Frieze, where blue-chip dealers schmooze their high-rolling clients in between sips of champagne. For starters, inventory cannot be priced above $10,000. There is no selection committee of veteran dealers choosing who receives a spot on the showroom floor. A good opening day at the Affordable Art Fair can top nearly $300,000—about half the price of a single Chris Ofili painting shown by David Zwirner at this year’s Armory Show. And yes, here, sometimes artists masquerade as their own dealers.