"This is the kind of item you either sell or you don't sell," said auctioneer Hugh Lester in a moment of candor - and moments of candor are precious when dealing with an auctioneer.

The item was an uncontested divorce, to be handled by Washington attorneys Eric Sayles (for the plaintiff) and Kathleen Johnson (for the defendant).

"Do I have an opening bid of $200?" asked Lester. All eyes scanned the house, and for a moment it looked as if this plum would pass by unplucked. But then an arm, soon to be identified as belonging to Geri Brandon, rose hesitantly in the middle of the crowd. There were cheers, and Brandon's arm rose still higher.

When it became clear that her bid, like the suit itself, was to be uncontested, Brandon stood to accept a prolonged ovation from several hundred fellow auctiongoers.

The divorce - along with dinner for two with "Arnold Schwarzenegger and a friend" (which went for $60), an autographed copy of Margaret Trudeau's memoirs by Steve Martindale ( $30), a tennis game with Bardyl Tirana ( $10, barely more than the cost of a court), and a "personally autographed crewelled Georgia ham pillow by Betty Talmadge ( $20) - was purchased Saturday night at "Dramathon," New Playwrights' Theatre's weekend of uninterrupted drama - which was interrupted about every 15 minutes by an appeal for contributions.

By the time Dramathon was sputtering toward its finish-line late last night, some 30 plays had been performed and over $17,000 netted.

Producing director (and principal huckster) Harry Bagdasian admitted that New Playwrights' could probably have made just as much money if all the volunteers who had put Dramathon together had gone to work picking lettuce or washing dishes instead. "But this is so much more fun . . . It gives us a chance to do our favorite plays and see our favorite performances, too."

Bagdasian said he had been at the American Theatre in L'Enfant Plaza, where Dramathon was held, since 3 a.m. Friday. He had snatched about four hours of sleep yesterday morning in the sound booth, he said, before going home to Dunpont Circle for a quick shave and shower. Dozens of other participants had multiple onstage or backstage responsibilities in a number of plays strung out over the long weekend, and often looked fairly strung out themselves.

Attendance was sparse during some of the 53 hours consumed by Dramathon, but response was lively. At the end of Ernest Joselovitz's 'Hagar's Children" Saturday afternooon, directed by Harriet Davis, "There wasn't a dry eye in the house ," Bagdasian said last night.

A moment later, an envelope was thrust into Bagdasian's hand. "This is the neat part of Dramathon," he said, examining the contents. "When you've walking up the aisle and someone slips something like this in your hand, $300. With a note - anonymous, no announcement please."

At the next intermission, a "miniauction" was held in the lobby to dispose of items that had failed to sell at Saturday's maxi-auction.

"A whole evening of one-act plays for your party," proclaimed the auctioneer as about 50 weary theatergoers huddled around. "Fifty dollars? I see a hand. Where was that hand?Oh. He was lighting his cigarette." The evening of one-acts eventually sold for $25.

"There's a white Buick Skylark with its lights on," said the auctioneer. "Virginia tags. . . ."

"Make them bid for it," suggested a member of the audience.

"Five dollars?" suggested the auctioner. And the owner of the Skylark stepped forward, forward, forked over a $5 bill, and left to find his car. CAPTION: Picture, Bari Biern takes a break from "Dramathon," by Fred Sweets-The Washington Post