While there may be a slump in the market generally, some people are waiting in line to buy houses.

Attracted by low down payment requirements and prices, at least 33 potential purchasers camped out in Columbia this week in front of a sales office to have first choice o $53,650-to-$69,100 town houses that go on sale at 10 a.m. today. Howard Homes Building Co. then will accept $500 deposits for the 131 houses it plans to build there.

The company, headed by Lee Rosenberg and Seymour Raphael, is building the new Spring Breeze subdivision in the King's Contrivance area. It has completed nearly 2,000 houses in the past 14 years, most of them in the low-price range. It currently is finishing 264 town houses in Hickory Hollow in another section of Columbia.

Aware that new home production and sales have been depressed in most parts of the nation, Rosenberg attributes Howard's success in attracting buyers to building "good" houses for-moderate prices. Most of the brick-faced, three-leveled houses offered have three bedrooms and 2 1/2 baths. The smallest, least-expensive model has two master bedrooms -- a design suited to house-sharing by unrelated buyers.

"We have developed, over the years, lists of persons interested in buying our houses," Rosenberg said. "When we are ready to make an offering, our prospective buyers already know about the houses [from those previously] built and have inspected the new site. So it's fairly routine to let them make a choice of model and site and take the down payment."

The Howard firm originally sent out 160 invitations to prospective buyers. The number of those waiting in line has increased almost daily in the past two weeks. Roll call has been taken every hour under a system that Rosenberg said was evolved by those in line. Stand-in representatives were allowed. Other persons are expected to join the group today.

Almost all of the prospective buyers already have filled out financial questionnaires -- "so we know that they are capable of buying," said Rosenberg. "We have FHA and VA loans [at 15 1/2 percent now] and also conventional financing, if desired. Under the graduated-payment FHA plan, the buyer can need as little as $3,950 cash."

Raphael said that sales contracts will be signed today at current prices with purchasers of the first 50 houses. Deposits will be taken on the other 76 houses on which prices will be established later.

The company is building 11 units to the acre at Spring Breeze. Houses have either 1,700 or 2,200 or 2,500 square feet of living area.

Rosenberg says his company trys to keep its overhead low, partly by having only eight employes on the payroll, and by keeping its advertising to a minimum.

The first Spring Breeze town houses will be ready for occupancy this fall.

The median price of new homes in this area has reached an all-time high of $97,200, the Metropolitan Washington Council of Governments noted this week, while the average sales price of all houses reached $112,546. Despite the high interest rates that have helped depress the market generally, sales of lower-priced houses have been good in recent weeks, some builders report.

At Burke Center in Northern Virginia, 389 sales have been made so far this year, working toward a 1981 goal of 803, according to executive Otis (Skip) Costin. Sales have been particularly strong at Burke Cove, a development of brick, garden apartments being built by International Developers, Inc., which listed 65 sales since April 24, he said. These are the first walk-up condomominium apartments offered in Burke Center. Prices range from about $45,000 for one-bedroom models to $78,000 for three bedrooms.

Ray Crace, head of the Pulte Homes division in Northern Virginia, said that combination town houses and apartments have been selling well at Antietam Woods in Lake Ridge, with prices ranging from about $55,000 to more than $60,000.

Also, the first 253-unit building at the new Montebello high-rise apartment complex south of Alexandria on Rte. 1 has been sold out for some months, and a waiting list has been developed for the second building that will be started in July by International Developers.

Ryan Homes reports that its sales have been consistently strong for its low-priced single and town homes in Newington Forest for several years.

Generally, builders and developers agree that smaller, lower-priced new houses have sold well despite high mortgage rates. At the same time, the market has been surprisingly good for new houses priced over $250,000.

However, the move-up market of houses priced from $125,000 to $200,000 has been slow in recent months, real estate agents say.