Heir hunters keep on the lookout for relatives with a claim to riches.

Heir hunters keep on the lookout for relatives with a claim to riches Don't call them. They'll call you.

"They" are an irascible gang of genealogists, attorneys and private detectives engaged in the lucrative business of inheritance. Call them heir hunters.

There is $48 million at stake -- the amount that Los Angeles County currently holds in trust for relatives of the newly deceased. And dozens of Angelenos who have no relation to anyone in particular, except the ability to find heirs, are actively in pursuit of a share of the booty. An heir hunter's share commonly amounts to between 20 percent and 50 percent of the total inheritance.

But don't expect them to advertise.

"American Research Bureau has been in business since 1935 and it has been a policy ever since then to not get any publicity," sniffs Mary Schwartz, the owner of the Los Angeles-based company.

Explains private detective Allen Song, another heir hunter: "Private detectives are the most paranoid people in the world."

One reason for the paranoia is the fear that inexperienced detectives will inundate the field. Unlike many other fields, finding heirs and heiresses can require no more investment than a telephone, a telephone book and the means to get to a good public library. In a competitive market like Los Angeles, the chance of such a low-budget operator surviving is slim, says Lee Cox, vice president of Tucson-based W.C. Cox & Co.

A difficult search requires an extensive genealogical library, travel and often the hiring of part-time investigators, he says. Occasionally, though, a one-man shop can pull in a healthy cash infusion by finding just one heir.

Los Angeles may be the best place to look for heirs in America.

"Los Angeles is probably the largest market heir hunters have," says Scott McWhinney, a Los Angeles attorney who specializes in these cases. "Just about any estate you look at here, where there is a piece of personal property, is going to be worth more than $100,000.

And local genealogical sleuths are apparently good at their jobs. Any inheritances left unclaimed revert to the state of California, but county treasures say that only $1 million goes unclaimed each year.

Ironically, the biggest competitor for local heir hunting firms is Los Angeles County itself. County public administrators are called in when there appears to be no will, or when an executor cannot be found.

Of the roughly 64,000 people who die in Los Angeles County each year, 1,700 are referred to county officials, says Gordon Treharne, senior deputy county counsel.

The primary job of the public administrator is to sell assets and pay creditors, but the county also tries to find heirs. It is successful in nine out of 10 such deaths.

"When you don't know where the heirs are, you state on the petition for probate that the heirs are unknown," says Gregory A. McCarthy, principal deputy in the county counsel's office. "That's when the heir hunters whip into action."

As many as a dozen heir hunters may be in county courthouses every day waiting for the public administrator to file a petition for probate. The petition reveals whether or not the county has found the rightful heirs, and it reveals the size of the decedent's fortune.

When the estate is substantial, heir hunters race to find relatives before their competitors. When they find the heirs they sign them to contracts promising the heir hunter a sizable portion of their new-found wealth before revealing which of the heir's relatives has died. In most cases, the hunters say the heirs have either never heard of the relative or lost contact long ago.

Even some of the most unlikely individuals have sizable estates.

Take the case of Mary Ellen Downs, who died July 16, 1986. Downs spent most of her time walking and sleeping in a Hermosa Beach park. But when county administrators stepped in because there was no will, they discovered Downs owned two homes, furniture and bank accounts valued in the neighborhood of $450,000.

County officials were unable to find relatives, but heir hunters, using extensive genealogical libraries, found six first cousins. None of the cousins knew the dead woman, but they are all still fighting for their share of her fortune, says Lonnie Armstead, chief of the county estates division.

Heir hunters also found Virginia Berndt's next of kin. Berndt, who owned $700,000 worth of property, had only one cousin and she was living in Yugoslavia.

County officials on their own solved another case, the stuff of which heir detective legends are made. A man who purported to be a UCLA student going by the name Jacques Chemur died in a plane crash in the late 1970s. But when Los Angeles officials called the man's mother in France to notify her, the reaction was genuine disbelief. Her son was standing by her side.

As it happened, the real Jacques Chemur had lost his passport not long after "a big swindle" in Paris, Armstead says. County officials believe the swindler was the UCLA student, whose real name was never uncovered.

The UCLA student, however, did have provable heirs. He had married two different women by using different names. The wives stepped forward, collected the money, and the case was closed.

Some cases remain a mystery.

One World War II veteran died with a fortune worth some $2 million. But investigations revealed that the veteran had taken on an assumed name, and no one was ever able to find his true identity or his heirs.

Each case can be fascinating, heir hunters say, because each tells the story of a real person's life. But the heir hunter's job is less than glamorous.

They spend the bulk of their time looking through telephone books, or combing through libraries, and sitting patiently in courthouses waiting for a list of the dead. Even when they find heirs who otherwise might not get their rightful inheritances, they are often scorned.

"Once the heir finds out who it is that died, they often want to break their contracts," says Willaim Erdmier, a Los Angeles heir hunting attorney.

"Heir hunters by and large do not have a good name."

It is a name they like to keep quiet, too.

"If you mention my name, we will get calls saying that `My grandfather had a farm and would you see what happened to it.'" groans Schwartz. "The people who really are heirs generally don't know anything about us until we contact them.

"People may want all day to be an heir, but if they are I'll find them. If they aren't, nothing they can do can make them heirs."

PHOTO : Stomping grounds: County Principal Deputy Gregory McCarthy