Builders Leonard Booth and Dominick Magarelli of Sunrise Associates plan to install solar hot water systems in 18 new house in Reston. Albert Leary Jr. of Scientific Solar Installations Inc., Falls Church, said that the project will be the largest number of solar installations in a tract of new houses in this area.

John Hancock Mutual Life Insurance Co. has provided $8.5 million in long-term mortgage financing for two office-research buildings to be constructed on Middlebrook Road in Germantown. Digital Communications will be the owner-occupant of the three-story buildings.

How to sell your own home, with or without using a broker, will be the topic of a two-part seminar to be offered at 7:30 p.m. Tuesday and Thursday at the Jewish Community Center in Rockville.

Building your own home will be the topic of a seminar next Friday and Saturday at the Manassas campus of Northern Virginia Community College. Walter Robinson of Warrenton will lead the seminar. For information, call 703-368-0184.

Walker & Dunlop arranged new permanent financing of $2.6 million for the Chelsea Square apartments on Backlick Road in Springfield. The 166 garden apartments were built in 1964.

The Windgate of Arlington town houses have been opened at South Walter Reed Drive and Arlington Mill Road in Northern Virginia. The Mill Road in Northern Virginia. The Anden Group is the developer. Prices begin at $65,000.

The District Real Estate Commission will hold license examinations for brokers and agents today at the Shoreham Americana Hotel.

The Mortgage Banker Association of America has adopted a policy opposing the use of municipal tax-exempt bonds to provide funds for home mortgages.

Embassy Park, a development of 90 luxury town houses, has been started on a part of the Glover tract between Massachusetts and New Mexico avenues NW as a joint project by Gerard M. LaVay and Donohoe Companies. Prices start at $182,000.