After a full day of cleaning houses all over town, Rosa Figueroa, a 25-year-old Dominican immigrant, spends four hours vacuuming the offices of $500-per-hour lawyers at 1201 New York Avenue NW. She is paid $8 an hour, with no benefits. After taxes, her wages would barely cover cab fare to her home off Colorado Avenue.

Now she is trying to change that equation as a bargaining team member of the Service Employees International Union Local 82, in contract negotiations that hold stakes for all kinds of low-wage workers and for virtually every user of office space in town.

An existing contract between cleaning firms and the union expires April 30. The two sides remained far apart last week, and if no deal is struck, a janitors' strike is likely, say sources on both sides of the table, though the talks are ongoing and are said to be relatively congenial. If the two sides can strike a deal, the price of higher wages or better benefits for 4,000 D.C. janitors would be passed through to tenants in the form of higher building service fees.

The issues involved are basic: The workers want more full-time jobs, better pay, and especially health benefits. The cleaning contractors say their expenses would spike by 60 to 70 percent if the union got its demands, and it says it is offering fair increases to pay and health benefits.

The skirmish is part of a larger battle, though, one that has played out in negotiations with janitors in Los Angeles, Chicago and Boston, over how businesses in the United States should treat unskilled workers.

The Washington negotiations are the latest in the "Janitors for Justice" campaign, launched by the service employees' union, which has had some success in other cities. The Boston contract looms particularly large in the Washington negotiations; in October, janitors there went on strike for 24 days and won much of what they wanted.

Moreover, janitors can easily attract public sympathy; unlike airline pilots or West Coast longshoremen, highly paid workers who have been involved in labor disputes in recent years, janitors are among the most put-upon workers. That helped the union in Boston, where political and even many business leaders sided with the janitors.

Another thing that makes this situation unusual is that the people who would ultimately pay for the higher wages and benefits are not even at the negotiating table. The janitors' union makes its case in part by stressing the relative strength of the Washington market for office space and the high rents that are paid. But landlords and building managers have no direct role in the contract negotiations; only the contractors they hire for cleaning services do.

"We have not been involved and don't know what they're going to do," said Thomas R. Hyland, senior vice president of the Apartment and Office Building Association in Washington. "We hope they can resolve the issue, but it's a matter for them to solve themselves."

And ultimately, the landlords are not on the hook for higher janitor salaries; in most commercial leases, those costs are passed along directly to tenants.

"If cleaning costs rise, it's going to be an add-on cost for tenants, one more thing that's going to run the bill up," said Christopher M. Campagna, an associate director of commercial brokerage Insignia ESG.

The real risk to D.C. office owners is that, as they already offer the most expensive space in the region, the higher cleaning fees would make them one notch less competitive with buildings in Virginia and elsewhere. Building management fees have already risen because of higher property tax assessments in the District and higher costs to insure buildings against terrorism.

What would the extra costs be for tenants? The union says that if it got the health benefits it seeks, the cost of janitorial services would rise by only pennies per square foot per year, a pittance in a city where commercial rents sometimes exceed $50 per square foot.

True enough, say the building contractors. By their estimate, the pay and benefits package the union seeks would raise the typical cost of cleaning to $1.60 to $1.70 per square foot per year from $1 per square foot.

"It's only cents, but that's still a 65 percent increase in the cost of cleaning," said Kevin Rohan, lead negotiator for the Washington Service Contractors Association and president of cleaning contractor Cavalier Services Inc.

The cleaning contractors have offered a limited package of health benefits, worth $3 million over a five-year contract, under which part-time workers with many years of seniority would receive benefits, with few benefits for new workers.

"We're proposing a reasonable, progressive approach that brings health insurance to part-time people, and I can't name another industry that has health benefits for part-time employees to that extent," Rohan said.

The strike in Boston offers hints of what Washington should expect if the two sides cannot reach a deal; they plan bargaining sessions on Wednesday and Thursday of this week and next week. Were there a continued impasse, the union could begin a strike soon after the deadline, perhaps on May 5, barring a deal to extend the current contract.

In Boston, the union launched an intense campaign to bring public pressure to bear for their side. Many politicians publicly endorsed the union's position, as did executives of such big Boston businesses asJohn Hancock Financial Services Inc. and FleetBoston Financial Corp. The SEIU hopes to do the same in Washington.

Less clear is how many of the 4,000 Washington janitors would participate in a strike. In Boston, there were contradictory reports of participation. Buildings continued to be cleaned with reduced staff, according to news reports. But the union said only 5 percent of janitors reported to work and that the contractors were able to keep cleaning by hiring large numbers of replacement workers, though the proportion crossing picket lines appeared to be considerably higher in some places, according to people who followed that strike.

"It varied a lot by building," said Andrew Sum, director of the Center for Labor Market Studies at Northeastern University.

Regardless, organizers in Washington say they are ready to hit the picket lines if they cannot reach a deal. "Our members are absolutely committed," said Valarie Long, president of the SEIU Local 82. "They see that every other major market has fought this battle and won. Nobody wants to go on strike, but people also don't want to be backed into a corner of living the way they're living."

Closings . . .

Unisys Corp. signed a lease for 270,000 square feet of office space at Plaza America III, next to Reston Town Center. The space, formerly occupied by Cable & Wireless, is owned by Intertech and Atlantic Realty. Trammell Crow Co. represented Unisys.

Neil Irwin writes about commercial real estate and economic development every week in Washington Business. His e-mail address is irwinn@washpost.com.

Last year, Boston janitors went on strike for 24 days. In Boston, picketing janitor Riccardo Perraulta offered free toilet tissue to passersby in front of one of the strike-target buildings in October.