Photographer Warren ("Don't look at the camera") Mattox returned from a recent vacation in Atlanta with a new appreciation of high housing prices in this area. The Northern Virginia homeowner brought back a free home guide with photos and brief descriptions of a four-bedroom rambler priced in the mid-$30,000s, a really large two-story "executive" home at $73,900 and a "super-split" in the low $40,000s. Additionally, Homeseekers Inc. in Atlanta publishes a picture brochure of homes for sale by owners. One nice-looking, large contemporary in "prestigious East Cobb area" is listed at $54,000. We Washingtonians can eat our hearts out if we can't move to Atlanta.

Builder-developer Milton Isen got nostalgic about the Homes of '78 in The Washington Post because he was represented by a $15,900 model house in the Yates Gardens section of Old Alexandria in the Homes of '48. He wrote: "You may not realize it but this is the 30th anniversary of that particular promotion. He says they were swamped with visitors but "didn't sell a damn house." Those houses probably now are being resold at four or five times that price in Old Town, where prices are appreciating faster than most areas. Isen's son, Robert, now 27, has dropped an art carer to become a third generation Isen in the realty business.

Ray Robbins, chairman of the board of the Air-Conditioning and Refrigeration Institute based in Arlington, said recently that the trade association of manufacturers of heating and cooling equipment expects to have a rating system for solar collectors within a year. Robbins, who is president of Lennox Industries, Inc., said that the program will include testing by independent laboratories - such as ACRI's.

The fifth annual Decorators' Show House, sponsored by the women's committee of the National Symphony, will be in a Pomponi0-built house on six acres of the Potomac River palisades just west of Chain Bridge on Route 123 in north Arlington. The unusually large house, inspired by the Carter's Grove mansion on the James River near Williamsburg, has been on the market for a reported $3.2 million, with the Joan Day-Vicki Bagley firm having the listing.

New adult classes are being offered at Columbia Technical Institute in Arlington, where director James F. Teets recalls that three of the four building Yeonas brothers (Gus, Paul and James) studied there before beginning their careers some years ago. Now George Yeonas (son of Gus) is enrolled for this year. Chief Fairfax County building inspector Joseph Bertoni also graduated from Columbia Tech, which formerly was located in D.C.

Down at the new community of St. Charles, which now has a population of 12,000 and a strong growth rate, the sewage is treated by a spray lagoon system on 150 wooded acres that are probably among the greenest in the area. The system was designed to handle 1.2 million gallons of sewage each day and the existing flow now is near 700,000. Four lift stations pump the sewage in the mains and into the lagoons. Chlorination takes place as the effluent enters the pumps of the land treatment system.

"This is so good we ought to invite the public," developer Milton Kettler said of the trade show held by area builder associations Tuesday at the Washington Hilton. The point he was making was that products displayed, from attic fans to whirlpool paths, would turn on the ultimate consumers - buyers of new houses. To go back a few years, the home shows at the Armory brought out the paying public for many years until a carny atmosphere took over. Could be that the public will be invited next year, for a fee of course. It might be worthwhile to hold over the show an extra day for public viewing.