CHAPEL HILL - The developers of 140 West Franklin have passed the halfway mark on units under contract and have begun negotiating leases for the project's commercial space.

Ram Realty Services has 75 of its 140 units under contract, Chairman Peter D. Cummings said in an interview Monday. That total includes 18 units priced to meet the town's affordable housing guidelines, as well as about four buyers who have purchased adjoining units and plan to convert them into a single home, he said.

The seven latest contracts have been signed since two 160-foot and 200-foot cranes arrived this summer to begin building the eight-story project.

"I think that has created more of a sense of urgency," Cummings said. "It gives you a sense - if cranes are on site and concrete is being poured - that you can go from point A to point B to point C."

The new contracts on Franklin Street stand in contrast to an industry survey Monday that found homebuilders remain pessimistic about the depressed housing market. But 140 West Franklin is not a typical project, Cummings said. Some buyers are downsizing; some are purchasing a second home. Last week a professor of geophysics and his wife signed a contract to buy a unit at 140 West Franklin after driving from their home in West Palm Beach, Fla., to Burlington, Vt., checking out possible places to retire.

Cummings said the project's location in the heart of the college town is the key to sales. He doesn't even think buyers are basing their purchases on near record-low mortgage rates of just over 4 percent.

"For our customers, mortgages are to some degree a non-issue," he said. "The majority are cash customers."

That's a difference between 140 West Franklin and downtown's other high-profile mixed-use condominium project, Greenbridge. Developers of that 10-story project have said some buyers backed out when they could not obtain loans. The project now faces foreclosure as the partners seek an investor to take on the debt.

Ram Realty has no debt yet on its project, Cummings said. The company is financing current construction with its own money and does not expect to draw on its Wells Fargo loan until late this year or early next year. About 55 percent of the $55 million project cost will be financed, Cummings said.

Once site excavation ends, workers will begin building the foundation and the underground parking levels. The building will begin to rise above its sidewalk fencing this fall, and the structures will be topped off early next year. General contractor John Moriarty & Associates Inc. expects to wrap up the project in the fourth quarter 2012, according to a news release.