When Chris and Robin Sorensen opened their first Firehouse Subs in 1994, they had less than $100 in their checking accounts.
"It basically had to work that first day," Robin tells CNBC.
The brothers, both second-generation firefighters, were broke even before they turned their vision of Firehouse into reality.
"We both loved to cook and we had actually had a bunch of ideas for other restaurants when we were younger. But it was all dreaming — it was never serious because we didn't have any money," says Robin, who was 26 when the flagship restaurant opened in his hometown, Jacksonville, Florida.