SAN DIEGO -- Converting apartments into condominiums helps many buyers reach the first rung on the homeownership ladder, but that step can come at the expense of longtime renters, a panel of housing experts said Thursday.

As housing prices across the county have shot up during the last several years -- the median price of an existing single-family home is now $500,000 -- condominiums have become a popular alternative.

The panel, made up of consultants, attorneys and planners, spoke about the popularity, perks and pitfalls of condominium conversions at a workshop hosted by the San Diego Association of Governments' Regional Housing Task Force.

Russ Valone, the chief executive officer of MarketPointe Realty Advisors, a San Diego firm that compiles data on real estate transactions, said that through the mid- and late 1990s there were only around 300 condominium conversions a year. By 2002, there were 619 in the county. Last year, there were 2,338.

"San Diego is the home of the condominium conversion market today," Valone said.

Since 2000, there have been 4,530 condominium conversions in east Riverside, Los Angeles, Orange and San Diego counties. Of those, 4,214 were in San Diego County, he said.

The average price of a converted condominium in the county is $278,000 -- far below the median price for a new home.

But those prices are still out of reach for low-income residents, who could be displaced when apartment buildings become condominium complexes, said Catherine Rodman, an attorney with the San Diego Advocates for Social Justice.

For renters, condominium conversions can be "confusing and frightening," she said. And state laws that require multiple notices -- often containing conflicting information -- only make the process more confusing, she said.

While the price of a converted condominium might seem a bargain to some buyers, many will still not be able to afford to buy the apartment they've rented, she said.

"It's a frightening thing for a tenant who may have lived in an apartment for five, 10, 15 years to get a notice of conversion and realize they have to move," she said.

Valone said that converting apartment units to condominiums does not make rental units scarce.

All of the conversions in the county since 1996 represent less than 1 percent of the county's total housing, Valone said.

"This option needs to be out there and available," he said.

But the panel also warned city officials at the workshop to proceed with caution.

Steven Rodick, the president of Condominium Consultants Inc., said that unless cities have specific language in their general plans concerning condominium conversions, they may have little say in the process and be forced to approve such projects in a short time frame.

There may be unintended consequences of condominium conversions, he said.

When two apartment buildings were converted to condominiums in Alpine, a number of renters were forced to move out of the East County community because there were no other rental units available, Roddick said. The unintended consequence was lower enrollment at the city's schools and at least one teaching position was cut, he said.

Contact staff writer Katherine Marks at (760) 740-3529 or kmarks@nctimes.com.