Take a drive through downtown Tampa, and you might notice a lot of "For Lease" signs.

That's a bad sign for people in the area who are trying to keep their businesses going, and now many of those business owners are saying something needs to be done.

According to our partners at the Tampa Bay Business Journal, two of downtown's skyscrapers are up for sale: Tampa City Center and Fifth-Third Center. Some experts say when - and if - they sell, it will say a lot about how the economy is looking for the city's central core.

But for the smaller businesses that thrive off of the companies that occupy these towers, filling in the vacant spaces is better done now than later.

Sean Smith, who has been managing the restaurant Fresh for the past two years, said those vacant spaces can be bad for business.

"It's not what it was two years ago," he said. "Things have slowed down. They've picked back up. They come and go in cycles."

On paper, though, downtown Tampa has seen a surge in leasing space. On average, downtown has just under 6.5 million square feet of office space. In 2010, nearly 20 percent of that space was vacant. Today, it's a little more than 13.5 percent.

That's still more than downtown officials would prefer. Ideally a downtown area wants to have only about 10 percent of its overall office space vacant.  However, it's still enough to keep Smith hopeful that better times are ahead.

"The city needs to do more to harbor and bring in more businesses and putting them into offices spaces at a more rapid rate than they are doing," he said.

Downtown Tampa is seeing a boom in residential space being constructed, which is good news for Mayor Bob Buckhorn's idea of a "live, work and play" scenario for downtown.