Bulk buyers have resold more than 60 percent of the coastal condominiums snapped up during the housing bust, according to a recent report.

The investment groups have unloaded roughly 3,200 of the 5,100 units that were in or near foreclosure, said CondoVultures.com, a Bal Harbour-based real estate consulting firm.

Many of the bulk sales occurred in Miami-Dade County. But as available properties there became scarce, the investors found deals in Broward and Palm Beach counties.

The supply of available condos is shrinking quickly, prompting developers to plan thousands of new units in South Florida over the next few years.

“Without the bulk buyers, we would not be talking about all this new construction,” said Peter Zalewski, head of CondoVultures.

Bulk buyers started by renting the condos but are reselling them for modest profits now that values are increasing, Zalewski said. He added that the groups are likely to keep renting some units, expecting prices to rise even more in the months ahead.

Some of the larger bulk sales involved Trump Hollywood, Las Olas by the River in Fort Lauderdale and 2700 N. Ocean Drive on Singer Island in Riviera Beach.

The 200-unit Trump Hollywood is sold out, Miami-based BH3 announced last month. The group took control of the development in late 2010 after developer Jorge Perez handed the 41-story tower back to the lender. Donald Trump still licenses his name to the building.

Lionheart Capital said last week that 2700 N. Ocean, now known as Ritz-Carlton Residences, has surpassed $100 million in sales.

Lionheart, a Miami-based private equity firm, bought 146 of the 242 oceanfront units in 2010. Prices range from the $700,000s to more than $10 million.

Sales are picking up, and buyers are discovering that they can’t wait indefinitely to decide, said Carolyn Block Ellert, a sales executive at the Ritz-Carlton Residences.

With less than a third of the units still available, “we’re well ahead of our projections,” said Ophir Sternberg, president of Lionheart.

A 2010 Florida law limited the liability for investors buying condos in bulk. Earlier this year, Florida Gov. Rick Scott signed a bill that extended the law until 2015.

By the end of this year, developers could propose as many as 10,000 new condo units across the tri-county region, according to CondoVultures.

Builders say demand justifies the wave of new construction. They’re banking on Latin American and other foreign buyers willing to pay as much as 80 percent of the cost of the condos before closing. In the past, buyers put down only about 20 percent.

But Deerfield Beach housing analyst Jack McCabe and other industry observers say developers could be making a mistake and overbuilding, which led to the housing collapse that started in 2006.

Despite the recent improvements in sales and prices, the condo market remains “very tumultuous,” according to McCabe.

“We quickly forget the lessons of the recent past,” he said. “We could very easily find ourselves oversaturated again, with thousands of units, if not tens of thousands.”