While builders and realtors report that the gasoline shortage has reduced the traffic of home buyers this month, the Washington Gas Light Co. says that the outlook for another kind of gas - for houses - continues to improve. The company has geared up its previously dormant residential marketing division to go out in the field to talk with builders about using gas in their new houses. While foreign suppliers are tightening shipments of oil for gasoline production, WGL says that its new souces include limited amounts from overseas.

The national certified public accounting firm of Kenneth Leventhal, which has offices here and in many cities, contends in a new report that medium-income home buyers can still do well by buying in outlying areas and commuting 30 to 50 miles. A farther-out house costs less and has a lower monthly mortgage, the firm points out. So if the house farther out is priced $10,000 less than a comparable house closer in, the owner would save $100 a month on a typical payment and have that much more money for increasing costs of gasoline. That assumes, of course, that you can get the gasoline.

Fewer that 36 apartments in the Appoline at 1330 New Hampshire Ave. NW remain unsold, according to Gary Nordheimer of the Cathedral Corp. The corporation purchased the 15-year-old, 241-unit building for $6.9 million from Abe and Irene Pollin and is converting it to condominium ownership. Prices range from the high $30,000s to the high $90,000s.

Begg Inc. has moved a sales office from the Wildwood Manor shopping center in North Bethesda to a location in the heart of Bethesda at 7101 Wisconsin Ave. Manager Carol Snowden said: "It makes sense to hug the Metro today. The nearby new station (at Old Georgetown and Wisconsin) is expected to be in operation early in 1981. Metro-related locations are increasingly important to buyers, too."