More than 2,500 business owners and professionals in Southern California, when in need of any manner of goods or services, are relying not on cash, checks or traditional credit cards, but a high-tech version of the ancient form of commerce, bartering.

Members sell their goods and services to each other for "trading dollars," credits kept in their computerized accounts and accessed with Trade American's red-and-blue credit card."We're like a bank. Everyone has a credit card and has to provide goods and services to have credit in the system," says Michael Ames, founder and president.

And, while all transactions can be handled by telephone or catalog, members who want to see merchandise can visit the only cashless department store on the West Coast. The Barter Department Store occupies a former clothing store in a shopping mall in Orange.

Ames, 46, a former health club executive, started Trade American 15 years ago and opened the Barter Department Store in 1980.

The store is packed with samples of members' wares, from cameras, cookware and jewelry to dried fruits, paintings and a stuffed deer head contributed by a taxidermist.

Catalogs also explain the services of attorneys, accountants, pool cleaners, cosmetic surgeons, picture framers and sex therapists.

The value in trading dollars of a product or service is based on retail prices.

The computerized credit system simplifies trading and makes possible swapping such unlike commodities as a restaurant meal for a copyrighted photograph of former President Ronald Reagan.

Members also can use their credit cards at the businesses of other members and at 70 other trading clubs around the country that have a reciprocal agreement.

Some trades are a bit unusual, such as delivering babies or performing funerals, but most transactions involve the mundane necessities of business life: office supplies, legal and medical services, printing, maintenance.

Beyond a convenience, Ames said bartering can help small businesses survive and prosper by offering goods and services they can't afford to buy.

He said a restaurateur paid for a $50,000 remodeling job with dinners. Member doctors, dentists and optometrists are used "quite heavily" by small companies that cannot afford to offer employees medical insurance due to skyrocketing premiums.

Barter clubs are more common than the average consumer might think. Trade American is one of about 300 "trade exchanges" nationwide. About 100 of the more established, thriving clubs belong to the American Association of Trade Exchanges.

Ames said he opened a department store because "the members were looking for place to display their products, so if a member came in he could see a lot of the things available in the bartering system."

The store also offers goods from bankruptcy and liquidation sales that Ames buys for cash and sells for trade dollars, thus providing more inventory for the members and more profit for the company since the goods can be purchased for below market value.

Operating expenses also come from the $500 membership fee, $100 annual dues and 10 percent commission on all transactions. The company did $8 million worth of business last year, Ames said.

Although located in a public mall, the Barter Department Store and Trade American are not likely to attract the average consumer.

Ames said businesses and professionals make better bartering partners than consumers.