It’s every “Antiques Roadshow”-worshipping estate sale junkie's ultimate fantasy: stumbling across a seemingly unexceptional painting or photograph at a bargain basement price only to have it professionally scrutinized and discover — holy Van Gogh’s ghost! — you’ve got a Sotheby’s-worthy piece of art on your hands.

It’s not every day that eagle-eyed treasure hunters unearth rare works (allegedly) created by iconic, mostly long-dead artists at charity shops, garage sales, flea markets, and their dearly departed great-aunt Henrietta’s attic. But it does happen and when it does, it’s often by accident.

Here’s a look at six recent headline-grabbing cases involving Goodwill Dali etchings, rummage sale Warhol sketches and a genuine flea market Renoir with a rather complicated backstory. And, of course, we wouldn’t want to leave out a Pollock (or is it?) snatched up for five bucks at a thrift store by a retired big-rig driver with an eighth-grade education and an endless reserve of pluck.

Have you ever snagged a rare or valuable piece of art for on the cheap from a yard sale or thrift store?

The booty: Rare Ansel Adams negatives

The source: Garage sale in Fresno, Calif.

Estimated worth: $200 million

OK, so the eventual outcome of this controversial “lost and found” saga turned out to be a false alarm, but it managed to stir up an international media frenzy and give hope to countless numbers of flea market fanatics that they could encounter a gold mine amongst the mounds of Precious Moments figurines and rusted power tools.

In the summer of 2010, construction worker Rick Norsigian came forward with a claim that he was in possession of 65 vintage glass negatives of landscape photographs taken by famed nature photographer Ansel Adams in and around Yosemite National Park in the 1920s and 1930s. Backed by a hired team of experts and an attorney, Norsigian believed the negatives he had purchased at a garage sale in Fresno, Calif., 10 years earlier for $45 — he bargained down from $70 — were worth an estimated $200 million.

A number of art historians, curators, appraisers and photography experts initially sided with Norsigian and were convinced that the negatives were the real deal, but they all didn’t agree that the value of the negatives was as high as $200 million. Beverly Hills art dealer and appraiser David W. Streets said of the find: “It truly is a missing link of Ansel Adams and history and his career. This is going to show the world the evolution of his eye, of his talent, of his skill, his gift, but also his legacy. And it's a portion that we thought had been destroyed in the studio fire.”

Not so fast, mon frère. Long story short, it was soon decided that the photographs were snapped by an amateur photographer named Earl Brooks, not Adams, after Brooks’ 87-year-old niece came forward to drop the huge bombshell. And because any good mystery isn’t complete without a high-profile lawsuit, Norsigian and the Ansel Adams Trust quickly embarked on a series of court battles, the former suing the latter for slander, and the latter suing the former for trademark infringement.

The booty: Original Jackson Pollock painting

The source: Thrift shop in San Bernardino, Calif.

Estimated worth: About $50 million

Here’s the story of a thrift store score so captivating that a critically acclaimed documentary film was made about it:

In the early 1990s, retired long-haul truck driver Teri Horton — described by The New York Times in 2006 as a “sandpaper-voiced woman with a hard-shell perm” — picked up an oversized painting at the Dot Spot Thrift Shop in San Bernardino, Calif., for $5 with plans to give the “ugly” find to a depressed friend as a gag gift.

“We were gonna get the darts and throw at it, but we never got around to it. We got to drinking too much beer and never went in the trailer and got the darts,” recounted the Ozarks-born Horton in a 2009 “60 Minutes” interview with Anderson Cooper. The canvas didn’t fit through the door of the friend’s trailer home, so Horton decided to hawk it at a yard sale. It was then that an art teacher from a local college spotted the painting and recognized it as having some very Jackson Pollock-esque qualities. At the time, Horton hadn’t the slightest idea who Pollock was. The rest, as they say, is history.

Horton’s fearless, highly publicized quest to prove that her drip-and-splatter purchase of unknown provenance was indeed the work of Pollock turned the art world upside-down and transformed the salty, 70-something Dumpster diver into an unlikely modern-day folk hero, “a pantsuited David flinging stones at the art world’s increasingly wealthy Goliaths,” as the Times put it.

To this day, Horton — aided by a team that’s included forensic art expert Peter Paul Biro and disgraced art dealer Tod Volpe — has failed to prove that the painting is a genuine Pollock. Some believe it is; some are unsure; others, including the former director of the Metropolitan Museum of Art, Thomas Hoving, are certain that it’s not. Horton has also failed to sell the painting, which she estimates to be worth in the ballpark of $50 million. (She turned down a $9 million offer from a potential buyer several years back.)

Andy WarholThe booty: Early Andy Warhol sketch

The source: Garage sale in Las Vegas

Estimated worth: $2 million

We’re going to go out on a limb here and assume that yard sales aren’t the main draw for British tourists in Las Vegas. But one visiting Englishman named Andy Fields’ decision to swing by a Sin City rummage sale — “It's always a fun thing to do, you find some very good bargains,” he told the BBC — resulted in him scoring an (allegedly) legit jackpot … and he didn’t have to spend six stressful, smoke-clogged hours in the bowels of Harrah’s to acquire it.

At the garage sale, Fields acquired five paintings for $5 from a “drug user” who claimed that his aunt was Warhol’s childhood baby sitter.

And here’s where it gets interesting: When he returned home to reframe his souvenirs, Fields discovered a sketch hidden behind one of the paintings. And as the story goes, the sketch, a portrait of French-Canadian crooner Rudy Vallee, is believed to have been the work of a very young Andy Warhol. The enigmatic pop art superstar spent a bulk of his childhood bedridden with cholera, a period when he taught himself to draw and listened to a lot of radio.

Explains Fields: “I was reframing one of the pictures and took the backing off and saw a picture looking back at me and recognized the bright red lips of an Andy Warhol. The experts think it is of historical importance because Warhol did not do pop art properly until he was 23.”

If the sketch is legitimate, its estimated worth is in the ballpark of $2 million. On the naysayer front, Warhol’s brother and a number of experts believe it to be a fake. Whatever the case, Fields is more interested in sharing the sketch than selling it, telling the BBC: “I want to keep hold of it — I collect art — but I don't want to sell it for a few years.”

In July 2012, the sketch was featured in an exhibition at the Royal West of England Academy in Bristol. Reads the RWA website: “Already causing much controversy concerning its origins, the portrait raises questions about provenance, value, and authenticity — all important considerations when new works by famous artists come to light.”

Pablo PicassoThe booty: Signed Pablo Picasso linocut print

The source: Thrift store in Columbus, Ohio

Estimated worth: About $7,000

Thanks to resellers like Zachary Bodish, it’s pretty darn hard to find decent mid-century modern furniture and accessories at charity shops these days. But even a seasoned thrift store scourer like Bodish, 46, probably wasn’t expecting to stumble across the rare treasure that he unearthed at a Columbus, Ohio, thrift store: an original linocut poster advertising a 1958 pottery exhibition in southern France that was designed, printed — and numbered and signed — by Pablo Picasso.

Bodish scored the framed linocut for $14 while hunting for Mid-century goodies and “kitschy art” at a Clintonville Volunteers of America store in March 2012. He didn’t think much of the print — he assumed it was a reproduction — until taking a closer look and embarking on some online reconnaissance work. As more and more signs began to point to “original,” Bodish started “shaking a bit.”

Bodish, who had been laid off from his full-time job, turned to restoring and reselling thrift store finds as a source of supplemental income. He explained to ABC News why he sold the rare Picasso print to a private buyer for $7,000: “I would have liked to have kept it, but I'm somewhat underemployed at the moment. I really needed the money. If it hadn't been worth very much, only $2,000, I probably would have kept it.”

Although it was never officially authenticated as one of 100 original prints before the sale, several potential buyers including a representative from Christie’s were more than happy to take the piece off Bodish’s hands. The final bidder “felt fairly confident” that the print was indeed authentic and even granted Bodish visitation rights.

And as for the guy who unloaded the print to the thrift store, he’s come to peace with his decision although some naughty words were apparently unleashed when he learned the print’s true value in the local newspaper. Retired schoolteacher Ed Zettler had kept the framed print, a housewarming gift given to him by a co-worker in the 1960s, wrapped in newspaper in his basement for years before deciding to donate it. “I’m glad that the guy that got it recognized something about it. I am pleased for him,” Zettler told the Columbus Dispatch. Mmm hmm.

flea market RenoirThe booty: Rare Renoir painting

The source: Flea market in Shenandoah Valley, W.Va.

Estimated worth: $75,000-$100,000

Surprise! Remember that box you bought at the flea market for $7 with the Paul Bunyan doll, plastic cow figurine, and the framed landscape painting inside? That Bunyan doll might be super-cute, but don’t disregard the painting … it just happens to be an original work of Mr. Impressionist himself, Pierre-Auguste Renoir.

That pretty much sums up the tale of an anonymous flea market patron from Virginia who, about a year and a half after making the purchase, decided to remove the painting from the ornate frame and throw it away. Her mother convinced her to get the painting appraised before doing so in case it was worth something. And after taking the painting to an Alexandra auction house for a consultation in the fall of 2012, the clueless gal discovered that the painting was really worth something … as much as $100,000.

Specialist Anne Norton Craner of The Potomack Company almost immediately ID’d the painting as a Renoir. After standard investigative work, validation by a Renoir expert and further research at the National Gallery of Art, Craner’s suspicions were confirmed: She was dealing with a genuine Renoir titled “Paysage Bords de Seine.” Said Craner of her first encounter with the painting: “She took it out of her plastic bag and it really looked like the real thing. There was beautiful light. It looked like a painting from 1879.”

The painting, believed to have once been owned by prominent attorney Herbert May, dropped off the radar in 1926. So where had it been all these years? And how did it wind up in a box of trinkets at a Harpers Ferry flea market decades later?

One explanation: The painting was pilfered from The Baltimore Museum of Art’s library. It just so happens that Herbert May’s wife, Saidie, was a major benefactor to the museum and the painting had been on loan there from 1937 up until the time it went missing in 1951. Although reported stolen with the police, the theft was never entered into an international registry of lost and stolen art.

Following the dramatic revelation uncovered by The Washington Post, the auction was canceled and the FBI took custody of the painting. BMA director Doreen Bolger told the Associated Press: “As this unfolds, we'll find out more about the ownership of the painting. If the painting is ours, we would be pleased to have it on view.”

So what about the woman who bought the Renoir for $7? She planned on visiting Paris with the money!

To date, no arrangements between the museum and the woman and/or The Potomack Company have been made public while the FBI investigation continues. If anything, the incident has managed to stir up long-standing tensions between the museum and the descendants of Saidie May.

The booty: Colored etching by Salvador Dali

The source: Goodwill store in Tacoma, Wash.

Estimated worth: $21,005 (final auction price)

Here’s a rare and valuable thrift store find that was flagged by a sharp-eyed, surrealist-savvy employee before it had the chance to enter the bargain bin:

Although her co-workers at a Federal Way, Wash., Goodwill drop-off facility didn’t think much of a bizarre etching that was left by a mystery donor in November 2012, Shea Munroe, a quality control officer responsible for sorting through art and collectables, knew exactly what she was dealing with: an honest-to-goodness Salvador Dali print, signed and numbered by the mustachioed madman himself. A certification of authenticity complete with registration number was attached to the print.

Well, hello Dali indeed! Did none of Munroe’s clueless co-workers ever spend time in a college dormitory?

After having the print — titled “Reflection,” the etching is number 126 of Dali’s 150-work “Cycle of Life Suite” — appraised and ensuring that it was not lost or stolen, the Tacoma Goodwill put it up for auction on its e-commerce site with a reserve of $999. Two weeks and well over 100 bids later, the print sold for $21,005.

Although the identity of the new owner of “Reflection” has not been revealed, Tacoma Goodwill CEO Terry Hayes told the News Tribune that several “big-name national people” had been involved in the bidding process. She tells the News Tribune of the anonymous donor: “I’d love to meet the person who donated it so I can offer my thinks [sic]. I would say that we’re so grateful, and we’re able to turn that donation into job training. Whoever donated that probably had no idea they would do so much good. It’s an incredible gift.”

Tacoma Goodwill e-sales manager Dylan Lippert further emphasizes how important the discarded Dali is to the organization: “Every once in a while something like this reminds us of how important what we do is. This is funding 10 scholarships for people with disabilities and barriers to employment. Just this one item will fund another 10 people. As of last week, there wasn’t funding for that. It’s amazing.”

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Click for photo credits

Photo credits:

Pollock: Amazon

Warhol, Picasso: Getty Images

Renoir: The Potomack Company