An unopened Nintendo game from 1988 found in this family's attic sold for $9,000 in online auction

Reno resident Scott Amos found a sealed cartridge of Kid Icarus, which sold for $9,000 at online auction.
Photo courtesy of Heritage Auctions

Sometimes cleaning out your attic can be worth it.

For 15 years, Scott Amos' mother had been asking him to come pick up boxes of childhood memorabilia he'd been storing in the attic of her Humboldt County, California home. This past Mother's Day, 40-year-old Amos fulfilled her wish and made an incredible discovery in the process.

While he was cleaning out the five boxes, Amos stumbled upon an unopened copy of Kid Icarus, a popular Nintendo video game from 1987. The game, still in a JCPenney shopping bag, had its original pricetag of $38.45, along with the receipt, dating the purchase to December 1988.

Amos consulted two video game experts, who agreed that the game would be worth a significant amount to collectors. He put the game up for auction through Heritage Auctions' Comics & Comic Art auction, and last week it sold for a winning bid of $9,000.

Photo courtesy of Heritage Auctions

"To find a sealed copy 'in the wild,' so to speak, not to mention one in such a nice condition and one with such transparent provenance, is both an unusual and rather historic occurrence," said Valarie McLeckie, video game consignment director of Heritage Auctions, in the statement. According to Heritage Auctions, there are fewer than 10 known sealed copies of Kid Icarus.

Denver-based Wata Games, a video game collectors' grading service, rated Amos' copy of the game an 8 out of 10. McLeckie says she's seen a lot of games come across her desk, but Amos' find stands out.

"It's certainly one of the most surprising just because of the origin of the game and how it was found," McLeckie tells CNBC Make It. "Typically, these higher-end, rare titles that we receive on consignment are from collectors who know what they have, and in the case of Kid Icarus, it was found in someone's attic with the receipts and the price sticker still on it so it also has a clear chain of provenance, which is very unusual as well in this type of collectible."

Photo courtesy of Heritage Auctions

Amos has sold other memorabilia in the past, but his most profitable sale before Kid Icarus was a Star Wars action figure collection he sold on eBay for about $200.

Though they may seem like junk to their original owners, vintage electronics – including video games, old-school record players, iPods and rotary phones – can be a hot ticket among collectors.

"If somebody has sealed titles that are within this same age, I would say, it's definitely worth looking into," McLeckie says. "Typically titles with higher pop culture relevance are ones that are going to be more highly sought after, such as the case with Kid Icarus, it's a bit of a cult classic."

Amos says his family plans to spend the money from the classic game on a classic trip: a Disney vacation.

"It's just been exciting and unbelievable, I mean, a $35 game sold for $9,000 is super exciting," Amos tells CNBC Make It. "We had a little watch party and all watched the auction live on the web. To think something that could've easily been thrown away or stayed up in the attic forever brought in that kind of income is a great story."

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