Two University of Maryland students and two local landlords have teamed up to fight a Prince George's County zoning change designed to restrict student housing rentals.

In a lawsuit filed recently, students Stephanie Stockman and Daniel Cones, president of the student government association, and landlords Donald Kirsch and Martha Kaye Dunn allege the zoning law discriminates against students and deprives landlords of rental income without compensation.

The law they are challenging requires houses with three or more unrelated students living in them to provide one parking space and a minimum 70-square-foot bedroom for each resident.

The law was passed by the Prince George's County Council in response to residents of neighborhoods around the College Park campus who have complained about noise and parking problems created by students. Homeowners argue that the proliferation of off-campus student housing lowers property values and diminishes a residential atmosphere.

Students say that because of a shortage of housing on campus, most students are forced to search for living quarters elsewhere. The new law, they said, will severely limit an already tight market.

Cones, a senior who lives off-campus with four other students, said as many as 3,000 students could be affected by the new law. Property owners have until July 1, 1991, to comply.

Deputy County Attorney Michael Connaughton defended the law. "In zoning laws you are allowed to make distinctions based on certain classifications," he said. "The Supreme Court has upheld zoning laws that limit the number of people living in a home in a residential area. The law says 20 unrelated people cannot live in a house together, but if it's two parents and they are prolific and have 20 kids ... well, that's legal."

Jim Kane, a member of the College Park Property Owners Association and manager of several area properties, said such distinctions cannot be allowed to become discriminatory. "The whole intent of all of this is to drive the students away from College Park, to satisfy a small group of people who absolutely abhor lifestyles that are different from their own," he said.

The seized Easton, Md., waterfront property of Filbert margarine heir Sandra Filbert Amos may go on the market next week.

When it is sold, the proceeds will be divided among the Easton Police Department, the Talbot County Sheriff's Department, the Maryland Department of Natural Resources Police, the Maryland State Police and the U.S. Justice Department.

The money will be divided based on the degree of participation of each agency in the investigation and conviction of Amos on cocaine conspiracy charges.

An open house recently at the five-acre property sponsored by the U.S. marshal's office attracted 53 local real estate agents and brokers.

"I was dumbfounded," said Curtis Hardick, supervisor of the national assets, seizure and forfeiture unit for the marshal's office in Maryland.

The house and acreage fronting Black Duck Cove were confiscated under a federal law that permits the seizure of property involved in drug trafficking. Local, state and federal authorities seized the house, land and personal property in June 1989.

Amos, heir to the Filbert margarine fortune, and Guillermo Moran, a Colombian immigrant who was the supplier of the local drug ring, were convicted by a federal jury of cocaine conspiracy and possession charges. Amos is serving a 14-year sentence at a federal prison in Lexington, Ky.

The house and land have been appraised at $750,000, but the property will probably sell for less because of the sluggish real estate market. Amos bought the property in 1982 for $260,000.

The house has a living room, dining room, study, three bedrooms, 2 1/2 baths, a Florida room and screened porch, attic space that could be converted into bedrooms, a five-bay garage and an Olympic-size pool. Amos still owns two other parcels of about 22 acres in the Easton area.

Amos is appealing the conviction.

May home sales in Virginia totaled 6,947, down 2.3 percent from the 7,112 sold in May 1989, the Virginia Association of Realtors reported. In the first five months of the year, 30,852 houses were sold in the state, down 7.4 percent from 33,310 during the same period last year.

In Northern Virginia, 2,367 houses were sold in May, up 20.5 percent from 1,964 during May 1989. But in the year to date, 9,411 homes were sold, 4 percent fewer than the 9,800 during the first five months of 1989.

A total of 1,934 permits for new housing construction in the Washington metropolitan area were issued during May, down 27.2 percent from 2,934 during May 1989, according to a study by Regis J. Sheehan & Associates, a management consulting firm in McLean. Permits for single-family units totaled 1,633, compared with 1,978 in May 1989, and multifamily unit permits totaled 301, compared with 680 in May 1989.

In the year to date, the 13,250 permits issued in the area represent an increase of 7.2 percent from 12,360 during the first five months of 1989. The increase is due mostly to an increase in multifamily permits: 5,217 permits were issued in the five-month period, up 45.7 percent from 3,581 in the first five months of 1989.

A total of 663 homes were sold in Prince George's County in June, off 4 percent from 692 in June 1989, the Prince George's County Association of Realtors reported. Of the 663 homes, 553 were condominium units, 7 percent fewer than the 595 units sold in June 1989. In the year to date, 4,360 units sold in the county, down 5 percent from 4,591 in 1989's first half. The average price was $122,300, up 7 percent from 1989; the average condominium price was $72,500, up 9.8 percent from a year ago.

IN THE BUSINESS ... Two out of three families that received housing vouchers were able to find quality housing using them, the Department of Housing and Urban Development reported as a result of a two-year experimental program in 17 large, urban public housing authorities and two state public housing agencies. The voucher is a federal rent subsidy for low-income families that makes up the difference between 30 percent of a family's income and locally set rent payment standards for the occupied units ... Corporate America Executive Suites of Reston was acquired by New York-based Executive Office Group, which supplies companies with furnished and staffed executive offices ... American Residential Mortgage Corp., a mortgage banking originator with offices in Sterling, Alexandria and Silver Spring, was sold by First Nationwide Bank of San Diego to Welsh Carson Anderson and Stowe, a New York investment firm ... The Northern Virginia Chapter of the American Institute of Architects announced its awards for excellence: Emerson G. Reinsch Library, Marymount University, Arlington; Alexandria Schools Rowing Facility, Alexandria; Grey Gables residence, Great Falls; and Redeemer Lutheran Church, Fredericksburg. ... Mount Vernon Realty plans to sponsor a Delaware Night in Annapolis at 6:30 p.m. Tuesday to extol the virtues of living in Delaware. For details, call (301) 266-9700 ... Century 21 of the Mid-Atlantic States added two new local affiliates: Century 21 Catherine Barber Realtor in Northeast DC and Century 21 Vista Realty of Vienna ... Manekin Corp. began building the fourth phase of 270 Technology Park, its 75-acre business park along I-270 in Frederick. The project will add 165,000 square feet to the 410,000 already developed ... J.H. Burton & Sons Inc. of Olney has closed its commercial landscape division. Most assets of that department, including equipment, field inventory and nurseries, were sold to Ruppert Landscape Co. Inc. of Ashton ... Prudential Preferred Properties plans to open its flagship office in Bethesda ... Pobiak Properties of Bethesda opened an office in Annapolis ... Real estate broker Ron E. Watkins of the Watkins Co. Inc. of Reston was fined $1,100 and ordered to surrender his broker's license by the Virginia Real Estate Board for violations of the state's realty regulations.

PERSONNEL FILE ... The Federal Home Loan Mortgage Corp. named Carl W. Riedy Jr. vice president of affordable housing initiatives ... Town and County Realtors Inc. of Fairfax appointed Gloria M. Carter vice president of a subsidiary, Town & Country Properties Inc. of Maryland ... Harkins Builders promoted John Wildrick to vice president of construction.