Power in numbers: a successful custom builder cooperative brings its formula to cities across the country.(CUSTOM BUILDERS)(Brief Article)

INSPIRED BY ITS SUCCESS IN pooling purchasing power, a group of Northern Virginia custom builders is helping others start their own purchasing cooperatives.

In 1996, seven members of the Northern Virginia Custom Builders Council formed a cooperative to negotiate better pricing with vendors and suppliers. It proved an immediate success when lumber prices increased as much as 50 percent during one quarter. Co-op members had better pricing locked in for 90 days, recalls Jeff Carpenter, president of Fairfax, Va.-based Monticello Homes and one of the co-op's founding members.

The group has since expanded to 50 members and has negotiated preferred pricing across a …