Arlington's contest to select a developer for the courthouse area has entered its final stage, with three major firms competing for the right to build a multimillion-dollar complex of offices, shops, apartments and a civic center.

The proposed complex, Court House Plaza, next to the Court House Metrorail Station, is envisioned by county officials as the centerpiece for a larger transformation of the courthouse area and as a guide for development in the Rosslyn-Ballston corridor.

"We hope to use this (project) as a way to begin to identify the corridor and set a standard of excellence which would be something to match or exceed in future development," said David Dantzler of the county economic development staff, who is project manager for the plaza.

The developers in the final running are the Cavalier Development Co., which includes the Lincoln Property Co. as the managing partner; the Charles E. Smith Co., in conjunction with the Artery Organization Partnership; and the Court House Plaza Development Group, a partnership of the Holladay Corp. and Kaempfer Co.

They are vying for the right to transform 6.4 acres of parking lots used by county employes in the adjacent courthouse, county office building and police-detention center into the multibuilding complex. The site is bordered by N. 15th, N. 14th and N. Adams streets and the courthouse complex.

Unlike land around other Metro stops in Arlington, the Court House Plaza site, valued at almost $8 million, is owned by the county, which has become a demanding landlord.

In announcing the contest for development of the plaza last February, the county established strict guidelines on building heights and the desired mix of residential, office, hotel, retail and civic center construction, as well as open space.

Office buildings, the county said, should not exceed 153 feet (about 15 stories), and apartment buildings and hotels should not exceed 180 feet (18 stories). The guidelines noted, however, that the County Board could approve a six-story extension.

The county also limited to 30,000 square feet a civic area designed for community activities, County Board meetings and offices for the county manager, county attorney and County Board staff.

Other guidelines include a minimum of 440 residential units; a maximum of 470,000 square feet of office space; 25,000 to 60,000 square feet of retail space; at least 615 parking spots for the public and county employes, over and above those earmarked for private use; and underground access between the plaza and Metro station.

In advertising the contest, the county also described the ambiance it hoped to achieve: "a sense of liveliness, activity and festivity, from early morning to late evening, especially after office hours, and on weekends . . . (and that would) combine civic participation in county affairs with work and recreation and create a focus for creative community activity, identity and pride."

One unusual twist to the development plans is that the county hopes to lease, rather than sell, the land to the developer selected for the project. But Dantzler said the county has "left it deliberately open to allow all parties to have a say on what's best for them."

Plans from the three finalists are being reviewed by a special, County Board-appointed panel that includes two County Board members, two residents and three experts in real estate, architecture and urban planning and project management.

The panel has set a hearing for Sept. 21 at George Mason University Law Center in Arlington for the three developers to present their proposals. Models of the different projects are on display in the courthouse lobby.

Originally, seven plans were presented to another County Board-appointed panel, which selected the three finalists.

The group reviewing the finalists' plans hopes to make a recommendation to the County Board by mid-October, with a final decision by the County Board by the end of the year. Under that timetable, construction could begin next year. No completion date has been set until a final choice of developers is made.

The three development teams and their plans, which would be done in various phases over several years:

* Cavalier Development Co., in partnership with nationally known Lincoln Property Co., also includes Arlington developer Preston C. Caruthers as a partner.

Michael B. Windsor, Cavalier's managing general partner, said the firm is proposing a $165 million plaza plan that would include two 15-story office buildings; a 240-unit, 17-story apartment complex for the elderly and a 200-unit general residential building of the same height; a five-story civic center; and a 270-unit, 17-story hotel to be built by an undisclosed national hotel firm.

In addition, Windsor said, there would be 50,000 square feet of retail space, the largest of the three proposals; a 77,175-square-foot open plaza; and parking for 2,114 cars.

In part of its proposal submitted to the county, the firm describes a plaza environment "carefully designed to incorporate a farmers market, filled with colorful awnings, tables of fresh produce and arts and crafts. Painters pick their models from people enjoying the weekend's activities, while visitors ascend the clock tower elevator to experience the spectacular view of Washington and the surrounding community of Arlington."

* Charles E. Smith Co. and the Artery Organization. Michael L. Reynolds, Artery senior vice president, said the proposal would be a $120 million to $150 million project of three squares connected by meandering, tree-lined sidewalks.

The three areas would be a civic or public square, a market or commercial square and a residential square that incorporates space for a farmers market. The design concept, the development team said, "combines the best aspects of a European town, with its tightly woven narrow streets and open plazas, with the tradition of a highly active American main street."

Reynolds said the proposal calls for two 12-story office buildings; 40,550 square feet of retail space; a 29,700-square-foot courthouse addition; a 228-room, 23-story hotel; a 2,025-car parking lot; and 461 residential units spread among three buildings. Two residential buildings would be 17-story condominiums, while the third would be nine stories, with 95 units for elderly residents. The latter would depend on the availability of federal funds.

* Court House Plaza Development Group is a partnership of the Holladay Corp, which would be responsible for the residential and commercial development, and the Kaempfer Co., the hotel builder.

Officials of the development group refused to comment on their proposal.

However, in plans submitted to the county, the development group proposes an office tower as part of a grand public concourse and a "great crescent" as a "major civic space not unlike Dupont Circle." An artist's rendering showed most of the buildings resembling the controversial Olmsted Building, scheduled for construction at the Clarendon Metro stop.

The plan, according to county documents, calls for 67,000 square feet of public space; 30,000 square feet of county space, including a 250-seat County Board meeting room; 25,000 square feet of retail space; a 200,000-square-foot office tower; 850 rental apartments; a 231-room hotel; and a 2,000-car garage. CAPTION: Illustration 1, A drawing of the $165 million proposal by the Cavalier Development Co., that includes office and residential buildings, a civic center and a hotel.; Picture, A model of the $120 million to $150 million proposal by Charles E. Smith Co., in conjunction with the Artery Organization Partnership, includes office and residential buildings, courthouse addition and hotel.; Illustration 2, A drawing of the plan offered by Court House Plaza Development Group, a partnership of the Holladay Corp. and Kaempfer Co., shows office, hotel and apartment buildings. The drawing shows most of the buildings resemble a controversial project scheduled for the Clarendon Metrorail station.