Fifty years ago, two restaurant owners in Ontario, Canada, traded a grilled cheese sandwich for a watercolor painting by a then-unknown artist. The painting just sold for $272,548 at auction.

Audrey and John Kinnear were regulars at Irene and John Demas' restaurant in the early '70s. The the four eventually struck up a friendship.

When the Demas family gave the Kinnears a grilled cheese sandwich in exchange for a painting John had brought in to the restaurant, it was considered a fair trade among the industry "newbies."

The painting this time wasn't one of John's personal art pieces, but rather a piece by his friend Maud Lewis, a painter from Nova Scotia.

"My husband made a deal with them to trade food for art. We needed art for our walls, and he needed to eat every day ... In the '70s, it was different. We didn't think so much about ourselves; we thought about our neighbors and how we could help each other out," Irene told The Washington Post.

"After a while, he started bringing in some of his art and asked my husband if we could trade for their lunches for his art. We happened to really love his art. He did some very beautiful watercolors ... he did a lot of European kind of stuff, English countrysides, and beautiful animals," she continued.

Though the four didn't exactly keep tabs on each exchange, their trade-offs were based on an honor system among friends.

Speaking to TODAY, Irene said neither she nor her husband were art experts or collectors, so they had no idea any of the art they had acquired might be of value.

"[John] came in with this very strange-looking art. It was on board, unframed, a very childlike, very primitive art that I'd never seen before. We just knew what we liked," she shared.

The Kinnears presented multiple pieces of art to the Demas family, but one simple painting of a man driving a black truck stood out. It was the piece by Maud Lewis.

"I was pregnant at that time. And [I thought], 'Well, if it's a boy, we can hang it in his room.' It turns out I picked the right one," Irene said. The Demas family indeed welcomed a boy, and they hung the Maud Lewis painting in his room.

Decades later, after John had passed away, the painting remaining in the Demas household. One day, the couple decided to have their art appraised and insured.

While connecting with various auctioneers for appraisals, Miller and Miller Auctions in Ontario made a determined bid.

The gavel slammed May 14, bringing with it a grand total of $272,548 for the Maud Lewis original painting.

"If it weren't for the grilled cheese, it just would have been another Maud Lewis painting coming up for auction," Irene told TODAY. "I know it would have gone. It would have broken all records because it is such a special and unique painting ... but I think it was the grilled cheese story that really let everybody in the world know [it] was there."

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