They file, every day, into the small claims courtrooms in Washington and the Maryland suburbs. Average citizens with a gripe against the dry cleaners, the storage company, the auto repair firm -- or each other.

Someone, they claim, charged too much, or didn't do the work promised or won't pay what is owed them. They've phoned and written letters but nothing has worked. So they've come to court. They win sometimes, but victory is no sure thing.

There's the young man who broke an apartment lease in Bethesda when one of his roommates moved out. He wanted his $425 security deposit back, but the landlord argued that it cost him that in advertising and lost rental income. The landlord won.

Or the Washington woman who complained she hadn't been paid in four months for the garage she was renting for storage space at $30 a month. The defendant, a lawyer representing a deceased client, said the woman had been abusive on the telephone. The judge told him to pay the bill from his client's estate anyway.

And the government worker who took a fellow employe to court, claiming he had co-signed on a $500 loan for his associate, who failed to pay it back. The judge told the defaulting employe to "tighten his belt" and begin repaying his friend.

He also warned the co-signer to think twice before he made himself liable again for someone else's debts.

Win or lose, they get their hearing before a judge at a minimal cost (as little as $2) and -- compared to other court proceedings -- with little effort. Complaints can appear without a lawyer (who might charge $100 or more) and the proceedings are more informal. Judges can bend the rules a bit, accepting evidence that wouldn't be allowed in other courts (such as bills and receipts), and sometimes guide both sides to an acceptable settlement.

Although they're dealing with small sums, many appearing in court are angry, and the remarks in front of the judge's bench can get heated. After hearing a series of bitter remarks one recent morning -- including a dispute over $500 by a couple that had split up -- D.C. Judge Nicholas S. Nunzio rested his head in his hands and said in mock exasperation: "It's enough to drive you nuts."

Still, it's the do-it-yourself system that was created to give the little guy a chance against the big guy, and for the most part it works.

There's another angle, however, to the system. The big guys also use the court -- department stores, utility companies, landlords and banks and finance companies. They're out to collect on overdue loans or missed installments or rent payments. They very often win.

Although some states ban corporations from suing in small claims courts, an estimated 75 percent of the 26,000 cases a year in D.C. Small Claims are filed by commercial firms.

"It's a collection agency for various business concerns as far as I'm concerned," says Willie Cook, executive director of Neighborhood Legal Services, which represents low-income residents notified to appear in court by a creditor.

Often the creditor's lawyer will meet with the defendant in the cour-room, before the judge's arrival, to arrange for payment of the bill. Some lawyers dispose of a dozen or more cases for several business clients in one morning. Cook is critical of the practice, arguing that unsophisticated defendants may sign agreements unaware that they might be better off going to trial.

Jack Scheurmann, who heads Law Students in Court, a program in which area law students also represent low-income defendants, agrees with Cook that the court sometimes resembles a collection agency, but points out that the poor might have a harder time getting credit in the Washington area if businesses didn't have the small claims court option for repayment problems.

In Washington, you can sue for up to $750. In Maryland District Courts, it's $500. There is no small claims court as such in Virginia, where General District Courts hear all claims up to $5,000.

One of the small claims court's chief problem areas, say those connected with it, is collecting the money after winning a case. You could wind up returning to court to have a debtor's property attached or a salary garnisheed.

Another big question is whether the person representing himself has a chance against another party with a lawyer. Lawyers cost money, and you could end up paying more than you are seeking. Administrative Judge Calvin Sanders of Maryland District Court 6 in Montgomery County maintains that the layman can win against a lawyer.

"The effectiveness of the lawyer," he says, "is reduced by the relaxed rules of evidence."

Cook warns, however, that because of the District's large body of consumer law, an individual might stand a better chance of winning with a lawyer. And in Virginia, where the relaxed rules of procedure do not apply if one side has a lawyer, Fairfax County General District Court Chief Judge Robert M. Hurst says most individuals confronting a lawyer without help end up losing.

In Maryland, Judge Sanders says he feels most people are satisfied "even when they lose. They've had their hearing."

And in the District, says Scheurmann, member of a D.C. Bar Association subcommittee studying operation of the small claims court, "the basic system is sound and working well." But "it needs to be tinkered with in terms of helping people collect."

The subcommittee is also looking into such problem areas as the need for more court night sessions and alleviation of long waits.

If you are suing, show up for the trial on time. If you're not there, your case could be dismissed. If you're being sued, you've also got to show up on time, or you could lose by default.

The judge or a clerk is apt to ask if you've attempted to reach agreement before coming to court.If you haven't, you may be sent out into the lobby for a few minutes to give it a try.

If you think you need a lawyer but can't afford one, you can contact the Legal Aid Society, Neighborhood Legal Services or the D.C. Law Students in Court program.

Bring any documents or photos you think may help your case, including damage repair estimates, canceled checks, bills, home sales contracts, etc. You may bring witnesses or have them summoned for a fee.

If you have a long wait in court, pay attention to what is going on. It may help you for your turn. Or you may want to drop in for a couple hours to familiarize yourself before your own day in court.