If you're one of the approximately 18% of Americans who shop at thrift stores every year, you may think you got a great deal snagging a designer dress for a fraction of the price. But you didn't do nearly as well as the people who stumbled on these five epic thrift store scores.

1. Declaration of Independence: Bought for $4, sold for $2.4 million

When a man shopping in a flea market in Adamstown, Pa., stumbled upon an interesting $4 picture frame, he got a lot more than he bargained for -- literally. The Philadelphian got home, removed the original painting -- a dismal country scene – and found The Declaration of Independence folded and hidden in the back of the framing. The original copy is one of just 26 out of 200 original printed copies known to have survived. In 1991, this thrift store find sold for $2.42 million at Sotheby’s — a 60,000,000% increase from that $4 pricetag.



2. Sleeping Lady with Black Vase by Róbert Berény: Bought for $500, sold for $285,700

A 43-year-old researcher at Hungary’s National Gallery was watching the movie "Stuart Little" with his daughter when he spotted a painting believed to have been lost. Two years later, Gergely Barki managed to get in contact with the former Sony Pictures set designer who told him that she had "picked it up in an antique shop for $500 because its avant-garde elegance fit perfectly with the Little’s living room.” After five years of the painting hanging on her wall, she took it down and sold it to a private collector who auctioned it at the Virag Judit Art Gallery in Budapest for $285,700 -- a 57,040% jump.



3. 360-year-old Flemish painting: Bought for $3, sold for $190,000

An 81-year-old South Carolina man who idenitfied himself by just "Leroy" made a score with his find at a Goodwill store. Leory purchased the $3 painting because he assumed the framing was from the 1800s and could be worth up to $100.

But the painting itself was far more valuable, dating back more than 300 years to a Flemish school. The piece sold for $190,000 -- a 6,333,233% increase!



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4. Vince Lombardi sweater: Bought for 58 cents, sold for $43,000

A Tennessee couple shopping at Goodwill in West Asherville, N.C., was in for a big surprise when they purchased a West Point sweater for just 58 cents. Sean and Nikki McEvoy had no idea that the sweater belonged to NFL Legend Vince Lombardi, the former head coach of the Green Bay Packers with five national championships and two Super Bowl championships to his name. "I saw the sweater on top of a pile, and I thought it was neat, high quality and a good deal for only 58 cents,” said Sean McEvoy. This past February the sweater was auctioned off in Heritage Auctions for $43,020 -- an increase of more than 7,400,000%.



5. Reported Jackson Pollock: Bought for $5; not sold yet

This find has been so controversial and famous that it became the subject of a documentary film. In the early 1990s, Teri Horton, a retired truck driver decided to buy her friend a gag gift she found in a San Bernardino, Calif., thrift shop. The plan was for the two of them to get drunk and throw darts at the painting. Luckily, Horton found out that it could be a Jackson Pollock painting. She was originally offered $9 million for the painting, but after 16 years she is still holding out for at least $50 million. The most expensive Pollock to date went for $140 million. While she hasn't yet received a cash return on her purchase, you could say the publicity she's received is priceless.

Editor's note: An earlier version of this story misstated return on investment by a factor of 100. Yahoo Finance regrets the error.

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