The garage has been described as "automated" or "robotic" because it would be built without ramps, leaving more room to park cars. Vehicles would be transported to and from parking spaces within the structure by mechanical lifts, and the walls have been designed with no windows because people would not go inside.

Hillman, who heads Southern Management Corp. in Vienna, Va., said the garage would still have the equipment that would move cars to parking spaces without the need for ramps. But instead of lifting cars to upper levels, he said, the equipment would take cars to spaces below ground. The design no longer includes 19 south-facing apartments.

Hillman's previous plans drew opposition from neighbors concerned that an 80-foot-tall building would dwarf the neighboring three-story rectory, a historic landmark that houses the headquarters of Preservation Maryland, and would block other buildings' views. Neighbors also expressed concerns that the garage would cause traffic congestion along Saratoga Street.

Hillman said he already has bought the equipment for the automated garage and that it was his son Richard's idea to install the "lifts" so they take cars down to park rather than up. He said contractors would need to dig 50 feet below street level to fit all 12 levels in, and that patrons won't actually drive their vehicles to the spaces. "The cars are in a vault, basically," Hillman said.

Tyler Gearhart, executive director of Preservation Maryland, and Rob Ross Hendrickson, a partner of a law firm with offices on the same block, both said Hillman's plan to build underground was an improvement over previous versions. Gearhart said he still had a few concerns about the underground garage, including its effect on traffic and the effect of excavation and construction on the rectory. Hendrickson said he'd like to see the garage rise even less than 35 feet above ground.

Gearhart added that Hillman deserves credit for saving and recycling a number of key buildings downtown for residential use, including the former Hecht's department store at Howard and Lexington streets, the former BGE headquarters at 39 W. Lexington St., and the former Standard Oil Building on St. Paul Place. "He's done good work."

Hillman, who has been working on the project for more than six years and three mayoral administrations, promised that it will fit in with the area. "It's going to be very attractive," he said. "I don't build schlock."