Osceola County's decision Monday night to boost its school impact fees to the highest by far in the state likely will ripple across Central Florida, driving some builders into adjacent counties while pushing up the price of existing homes.

Facing an exploding student population and short hundreds of millions of dollars to build schools, Osceola county commissioners say they had no choice but to triple their fee -- raising it from $2,828 to $9,708 for a new single-family home.

The commission vote Monday night was unanimous, even though Commission Chairman Paul Owen suggested postponing the vote for a week. Commissioners, however, decided they couldn't delay because they feared the state Legislature might act on a proposed bill that would freeze impact fees for six years and then do away with them.

Osceola's vote may have an almost immediate effect on Central Florida's housing market.

The biggest tremors could hit the booming Four Corners area of northeast Polk, which has a similar housing market, lots of available land and much lower impact fees.

A builder pays a $1,607 school-impact fee for a single-family home in Polk. Developers recoup impact fees in the prices they charge buyers.

"I think it is reasonable to believe when you have counties that are immediately next door to each other, you could see a substantial shift," said Owen Beitsch, executive vice president of Real Estate Research Consultants. "There are parts of Polk County where the buyers are interchangeable."

Some Polk officials were surprised at the size of Osceola's increase.

"That is unbelievable," said Polk County Commissioner Don Gifford.

Gifford, who is in the construction business, says it's natural to expect builders to look toward Polk. They'll "go where the land and services are less."

It wouldn't be the first time that what one county does has an effect on its neighbors.

After Orange County declared large tracts of rural land off limits to development in 1990, developers started leapfrogging to Osceola and Lake, where development restrictions were looser.

Orange planning manager Chris Testerman doesn't think that Osceola's impact-fee increase will have the same type of influence on the market, at least in Orange.

"There's that potential, but there are other market factors to consider," Testerman said.

A local government's land-use regulations -- and willingness to rezone rural land -- often plays a bigger factor on where developers decide to take their projects, Testerman said. v Beitsch also stressed it would be impossible to predict exactly what will happen because of Osceola's fee increase.

Among the beneficiaries will be owners of existing homes in Osceola and adjacent areas, who will almost certainly increase their asking prices because of the higher cost of new homes in Osceola, Beitsch said.

"There are clearly some artificial increases in prices that aren't justified by the quality in product," he said.

Still, Osceola officials deserve some credit for trying to get a handle on the demands of growth, Beitsch said.

"We really have some major growth-related problems in this state," he said. "I'll sure be the first to say that I don't have all of the solutions."

The problem, homebuilders say, is that they are increasingly being asked to pay for those solutions through impact fees.

School impact fees are charged in 19 of Florida's 67 counties, according to a consultant's survey this year. Until Osceola's increase goes into effect, buyers in Lake County pay the highest school impact fees in the state -- at $3,489 for a new home.

Lake raised its school impact fees this year, and Orange is considering an increase of its $2,828 fee.

Osceola's population grew 60 percent during the 1990s, while Lake County's grew 38 percent.

Osceola's higher impact fee will put the cost of a new home out of the reach of some buyers, predicted Tom Lagomarsino, executive director of the Home Builders Association of Metro Orlando.

Rubin Sanchez, who said he is looking to buy a house in Osceola County this year, agreed.

"That $6,000 [increase] might keep me from buying a home," he said Modnay night. "I have kids in school. It's a double-edged sword."

Some developers also may decide to build higher-end homes, where the market won't be affected as much by a $7,000 increase in the cost of a new home, he said.

"Our big concern is the fact that your kids and my kids and the young couple struggling to save some down payment and get into a home of their own, won't be able to do it."

Christopher Sherman of the Sentinel staff contributed to this report. Joe Newman can be reached at jnewman@orlandosentinel.com or 407-420-6140.