It is still early morning on a cool October Sunday, but the dealing at the flea market in the Mall in Columbia parking lot is already in full swing. Prices are flying faster than the leaves in the fall wind.

"Everything is half of what it's marked," a dealer clues a shopper inspecting glassware.

Nearby, an "Impeach Nixon" bumper sticker is marked $8, and the dealer lets you know she wants $5, but will take $3.

A man asks a dealer if she will take $20 for a Kennedy-Johnson inauguration button. She winces and says, "That's my best one, no, I can't take less than $25." Coolly, he walks away.

It's ruthless dealing here in the suburbs.

The Columbia Market is a tradition dating back to the beginning of this 20-year-old planned community.

Every Sunday from April to October, as many as 200 vendors and 10,000 customers from several states gather under the covered parking lot at the mall. On Sunday they will conclude the season doing what folks at flea markets do best: dealing.

"It's an adventure. There's always that possibility of 'finding something.' That's what I love about this business," said Keith Huppart, a dealer from Baltimore who has been selling at the flea market for eight years.

"This is a very good market; it attracts a lot of people," said Kathy Baker of Mifflinburg, Pa., who, with her husband Ray, sells quilts made by Amish and Mennonite women.

"We average two quilts every Sunday. We've been to a lot of craft festivals and we don't sell as much as we do here," she said.

Sellers and buyers at the market agree that a major factor in the market's success is its reputation for quality merchandise.

"This is better quality than most markets; they don't have tables full of sweatshirts," said Jim Browne of Durham, N.C. He and his wife Donna patronize the flea market on visits to relatives in Silver Spring.

On this Sunday they bought a "Jewel Tea" casserole dish for a collector friend in North Carolina.

"I used to go to other flea markets, but this is the only one I go to now," said Linda Wolford of Severn, Md., who collects figurines.

"We usually find what we want here. Columbia is a high-priced place, but the flea market is really good."

"They've got glass here for $2,000," Barbara Benfield, a dealer from Landover Hills, said when describing another dealer's wares. "I know this is a cliched phrase, but there are a lot of yuppies here who have money to spend. And they want quality."

Hubert A. Bellman, the organizer of the market, said he discourages "yard sale" dealers by restricting merchandise to antiques (items more than 100 years old), collectibles (memorabilia from more recent years) and crafts (handmade items). He sets the booth rental fee at $35 -- high by flea market standards.

"I'm not saying it's 100 percent pure antiques, but in comparison to other markets, it's perfect," Bellman said. "When you attract a high quality of dealer, you attract a high quality of customer."

Bellman's standards still allow for a lot of diversity. Near a booth where antique oak dressers are selling like hotcakes, Donny and Marie Osmond dolls are for sale along with their entertainment center, clothing and accessories for a mere $18.

"Goldwater for President" pencils command $1, while an ornate oak mantle mirror has "$295 NEGO" soaped on it.

Carl Zambon and Mariann Percy of Cockeysville, Md., are regular customers. They said they like the market because of the variety of merchandise, the reasonable prices and the easy parking.

"There's almost nothing we don't collect," said Zambon, who has come to the market for eight years. "We go to a lot of flea markets, and I think it's one of the best in the Baltimore-Washington area. There's always some little bargain you can find. I have never walked away from here without buying something."

The dealing begins in the wee hours of Sunday morning. Jim Avery, a dealer from Takoma Park, said distinct groups of customers pass through the market every Sunday.

"From 5:30 a.m. to 6, you've got the hard-core dealers {coming to buy for their own stores}. They're out here with flashlights while things are being unpacked. From 6 to 7 are the not-so-hard-core dealers. From 8 to 9 is the crowd that doesn't go to church. The after-church crowd arrives about 11 and from 12 to 1 are the late sleepers," Avery said.

Many dealers say it is difficult to predict which Sundays will bring in a high volume of sales. Lorraine Przywara, an antique dealer from the Baltimore suburbs, said she has done some of her best business at the market on rainy days under the shelter of the covered parking lot.

"Rainy days are the best. You can't cut the grass, you can't play tennis, so what do you do? Come to the flea market," Przywara said.

There are the people who buy, such as Robert Cecil of Beltsville, who was lugging two large bags to his car one recent Sunday.

He said he shops at the market because "it's always well set-up here, and there are nice things, not garbage. And people are willing to make deals."

Then there are those whom Huppart described as "serious lookers. It's like going to a museum for them."

As he spoke, a woman at his booth picked up a container made of green Depression glass and carefully examined its curves and ridges.

She took the lid off. She turned it upside down. She turned it around and around. She put it down and walked away.

Although the dealers continue to sell late into the afternoon, most of the crowds (and the best deals) are found in the morning, according to the flea market regulars. This makes for a convenient relationship with the mall retailers, whose shops open at noon.

When the Maryland blue laws were repealed this year, making way for Sunday shopping, a rumor spread that mall managers, who rent the space to Bellman, were thinking of shutting down the flea market. Mall officials said they received calls in support of the market.

"Our major concern was parking and congestion from the flea market, but that never materialized," said Joseph Ochs, vice president and general manager of the mall. "We weren't sure what kind of impact the market would have on Sunday shopping. We decided we would take this summer and see how it went. They were able to exist side by side; they complement each other."

He said the market will continue next year. "We feel the antique market provides an addition opportunity for people who are shopping. There are things at the market you don't find at a typical retail store."

Bellman said the market has changed during the past two decades. He said the customers expect more today and the booths are more professional-looking. Furniture from the 19th century was popular in the late 1960s, while 1950s furniture and memorabilia are in high demand today. Folk art, primitive pieces and glassware are named by dealers as sought-after today.

There is one type of item Bellman said never goes out of style.

"Anything that is very, very good and very, very cheap."