ORLANDO, Fla. -- Mortgage fraud has gotten so bad in Central Florida, the FBI is now focusing locally.

Complaints of mortgage fraud have more than quadrupled in the last three years and the FBI and state investigators are working several major cases involving local homeowners. Wednesday, the FBI revealed how some of the cases work and what they're doing about it.

The FBI says scam artists go to the courthouse and get a list of folks in pre-foreclosure. They offer to get them out of financial trouble, but really take their money and run. Agents are also investigating lenders accused of taking advantage of homeowners.

Daniel Jackson says he was duped out of thousands of dollars by Countrywide Mortgage Company.

"It's just been one big headache," Jackson told Eyewitness News.

Jackson says Countrywide kept charging him late fees even though he was paying on time.

"It was basically legalized extortion," Jackson said.

Florida's attorney general thinks it may be illegal. After getting 150 complaints, he's launched a full investigation into Countrywide's practices.

Unsuspecting home buyers are targets, too. Orange County detectives said a family of four stole people's personal information and then used it to get mortgages worth millions of dollars.

Mortgage fraud is growing so fast, the FBI is now focusing on Central Florida. Special Agent David Couvertier told Eyewitness News desperate homeowners facing foreclosure are especially vulnerable.

"Easy prey, that's the bottom line. They are easy targets for a quick turnover on the profits," he said.

In a rare interview, Couvertier explained how one common scam often works. A con artist will approach a homeowner in financial trouble, promise to take the title and rent the home until the owner gets back on his feet and can re-buy the home. Instead, they pocket the rent money and walk away and the home falls into foreclosure.

"It leaves the original homeowner with very little recourse and more debt," Couvertier said.

FBI agents are working undercover, posing as homebuyers and lenders to uncover fraud. They said they are working numerous cases in Orlando.