On a quiet, tree-lined street in Huntington, Joshua Klein sat in his SUV for 12 hours straight, watching the front door of an elegant two-story home. He drank one Pepsi after another to stay awake, hoping to catch a married woman leaving her suspected lover's abode.

An apprentice private investigator, Klein had spent two weeks tracking the woman, whose husband had hired Klein to find out whether his other half was having an affair.

When the woman finally emerged, she was holding hands with a tall, dark, handsome man. They kissed and hugged as Klein snapped pictures. His work, at last, was done.

Despite the successful outcome, the case was just Klein's third all year, leaving him struggling to pay rent and credit card bills. A former landscaper, Klein turned to investigations after being laid off in summer 2010, but can barely make ends meet in a field where income hinges almost exclusively on caseload.

And he's far from alone.

Long Island has more licensed private eyes than any area in the state, but those 941 suburban sleuths, as well as numerous apprentice investigators like Klein, are finding it harder than ever to drum up business, according to several struggling investigators.

The troubled economy has left fewer people willing to shell out up to $100 per hour to have their spouses tailed, long-lost relatives located or potential business partners screened, the private eyes said.

Reasons for decline

Adding to their woes was the passage of New York's no-fault divorce law in 2010. The legislation removed the need for couples to prove infidelity or other marital wrongdoing to obtain a divorce. As a result, matrimonial investigations are no longer a reliable source of income for many sleuths.

"I got into this business because I thought I could make a living, but it seems like people need private investigators less and less," said Klein, 34, of East Farmingdale. "It's a dying art around here."

The lack of business for private investigators is partially a result of their sheer numbers. With 519 private eyes licensed in Nassau and another 422 in Suffolk -- the two highest totals among New York's 62 counties -- there simply isn't enough business to go around, investigators said.

Many PIs retired cops

Many private eyes on Long Island are retired police officers who turned to the work as a way to stay busy and supplement their pensions, said Paul Massimillo, a retired NYPD detective who owns Long Island Investigations in Massapequa.

Detectives who once hunted New York City's murderers and thieves now find themselves staking out cheating spouses -- if they're lucky. Mostly, though, local private eyes handle routine insurance fraud cases, run background checks and sniff out small-scale thievery.

People who once hired investigators are increasingly turning to the Internet, where formerly hard-to-find records are just a keystroke away.

"I get calls every single day from licensed PIs [private investigators] on Long Island looking for work, because it's very rough out here," said Massimillo, 51, who has been a PI since 2005. "There are PIs going out of business every day."

Life wasn't always so tough for Long Island's private eyes, several said. The job was once well-paying and exciting, with deep-pocketed clients shelling out huge sums for cases that could take months to crack.

Independent sleuths in the 1980s and 1990s could earn more than $100,000 a year through word-of-mouth and ads in the Yellow Pages, several of them said. Now, those same investigators are scraping to get by, their ads lost in a jumble of Google search results.

A dying market

"The market for this business on Long Island is dying and it's dying quickly," said Joe Brandine, 64, of Babylon, who is widely considered the dean of Long Island private investigators. "There's not much pie left to cut up."

His caseload has decreased about 70 percent since 2006 -- with no bottom in sight. The squad of 15 to 20 investigators he once employed has dwindled to two.

Some private eyes try to set themselves apart by finding an off-the-beaten-path specialty. Andrew Spieler, a retired NYPD officer from East Meadow, snoops on teenagers for their worried parents, in addition to handling more routine cases.

He was recently hired by a couple who wanted to know how their 18-year-old daughter could afford a new car with tips from her waitress job. Spieler followed her to the restaurant where she supposedly worked -- then watched her quickly leave through a rear exit.

The investigator tailed her to a nearby strip club and discovered her real job: topless dancer.

But for all of their cracked cases and tales of intrigue, many private eyes say the glory days of Long Island snooping will never return.

"It was a good business while it lasted," Brandine said. "But it's not lasting."

REQUIREMENTS FOR A PRIVATE INVESTIGATOR'S LICENSE:

Be at least 25 years of age and a principal in an investigative agency

Pass the private-investigator examination within two years of applying for the license

Have either three years' experience in the business or three years' equivalent experience, such as police work

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