Northern Virginia tenants forced out of their apartments by condominium conversions may soon be entitled to relocation payments under a controversial bill that received final approval today in the Virginia General Assembly.

The bill, sponsored by Del. John H. Rust Jr. (R-Fairfax), would allow Northern Virginia localities to force condominium developers to pay relocation costs of up to $500 and to provide extended three-year leases to elderly and handicapped tenants.

Both measures have long been sought by Northern Virginia officials beset by the social consequences of widespread condominium conversions. But their victory today was marred by another feature in the same bill which they fear will deny them a forum to negotiate with condo developers.

That provision would forbid local governments from using their zoning powers to hold up approval of condominium conversions in exchange for concessions for tenants and future condo owners.

Officials from Fairfax, Arlington and Alexandria lobbied vigorously against the measure, charging it would leave them without leverage against developers. Although that opposition was softened by the Senate amendments providing for extended leases and relocation payments, it has not gone away.

"The bill certainly is a loss to us philosophically," said Arlington County Board member Ellen Bozman. "The state is stepping in and saying 'no, no, localities, we don't trust you to govern yourselves.' "

"It's going to hurt us more than help us," said Fairfax County Supervisor Audrey Moore of the final bill. "Fairfax is going to be flooded by these condo conversions and we don't have any kind of long-term protection."

Moore and others were surprised today when the House of Delegates approved the Senate amendments allowing Northern Virginia to require relocation payments and extended leases. Only last week, the House had rejected an amendment to the Alexandria City Charter that included the relocation costs provision.

The General Assembly traditionally has resisted giving local governments power to enact tenant legislation, arguing that government should not intrude on the "property rights" of landowners.

But the amendments to the Rust bill, supported by the powerful Virginia Condominium Developers Association, sailed through today without opposition. "I suspect two-thirds of the membership didn't understand the Senate amendments, myself included," said House Majority Leader Thomas Moss (D-Norfolk).

Del. James F. Almand (D-Arlington), who sponsored a tenants rights bill that overlaps with the amendments to Rust's bill, said today the House vote was "a big step forward" in the slow battle to improve tenants rights in Virginia.

"The amendments to the Rust bill were very good for tenants and the rest was good for getting support for them," he said. "That's the way it often works down here."