The Prince William Board of County Supervisors will vote on whether to change the county's purchasing rules so that all public repair jobs of less than $500,000 would go to one company.

The county currently requests bids for every job that costs more than $100,000, except in emergencies, and the board must approve each contract.

Under the proposal, going with one contractor would allow county staff members to bypass the board when a problem arises, such as a leaky roof, said Carol Scarton, the county's purchasing manager.

The county fashioned the proposal by looking to Fairfax County, the only other county in the state that Scarton could recall having a similar procedure.

"We're modeling it somewhat after Fairfax, but it's our own thing, too," she said.

The board is scheduled to vote on the changes Tuesday at its meeting at the McCoart Administration Building.

The new procedure, called a "job order construction contract," would save the county time and money, Scarton said. Each contract takes an average of 11 weeks to implement, beginning with the bidding process and ending with board approval, Scarton said.

Fairfax County has several contracts in place for routine maintenance, but major capital projects must still be approved by supervisors, said David Dise, Fairfax's deputy director of purchasing and supply management. It's a way to streamline the process, which can take several weeks, he said.

"You don't want citizens to suffer waiting for a leaky roof in public housing to be fixed," Dise said.

State law guides purchasing, but each county can adopt its own version "so long as they allow competitive bidding," Dise said.

In Prince William, there are an average eight projects annually that cost less than $500,000 that could benefit from the change, Scarton said. Thomas Bruun, assistant director of public works, pointed to work on historic properties, such as the 260-year-old Rippon Lodge, the oldest home in the county.

"It's little things, but it adds up," Bruun said.

The proposed changes in the regulations also would require the contractor to set a price at the beginning that could not be amended from project to project, saving the county more money, board Chairman Sean T. Connaughton (R) said.

In other business, supervisors will consider several changes to the zoning ordinance. One would clarify the roadside sale of seasonal goods to mean "items harvested and/or sold on a seasonal basis," including Christmas trees, pumpkins, summer produce, seafood, fireworks and potted plants on Easter.

Roadside peddlers interested in selling flowers on Valentine's Day and Mother's Day argued a few months ago that the law was too vague and unfair. The proposed amendment would officially make the roadside sale of goods for those occasions illegal.

To make way for Prince William's first winery, a proposed zoning amendment would establish regulations requiring a minimum of 10 acres and limit wine tasting and food sales to 20 percent of the total gross income.

Another zoning amendment would allow residents to build ramps for the disabled into setback areas. Currently, residents aren't allowed to encroach upon a setback.