DELRAY BEACH, Fla. -- Architect Sergio Santos has an impressive portfolio of work, including residential buildings and college dormitories. His large spaces are bold. But it is his smallest project that has gotten a lot of attention.

After losing his job in January, Santos tried renting an apartment in Delray Beach.

"I had to save money as much as I could by living cheaply," he told Local 10's Jonathan Vigliotti. "I came to this building to see the bedroom next door but I couldn’t afford it. So, I offered to rent the closet for $150 and the landlord accepted."

In April, Santos moved in and started renovations. In 16 days an empty box was transformed into an apartment.

"It’s 77 square feet. It’s a very, very tiny space,” he said.

He said the trick to making a small space work is to give every addition a dual function. A shelving unit he built, for example, turns into a staircase that leads up to a bedroom and television room.

"It was hard to make this space functional the way it was. It took three days just to plan," Santos said.

Santos used wood scraps and other found objects to assemble his home. Total costs came to $64.

The space includes an office, veranda with a window, a sitting room, kitchenette and closet space. The room is too small for a bathroom so Santos shares a bathroom with the apartment's owner.

"I never knew I could be so happy in such a small space. I'm just feeling so happy here,” he said.