At one time just sparsely attended convocations of awkward teens and adults, comic conventions have evolved into makeshift marketplaces for an unusually torrid asset: comics.
First-edition copies of characters like Batman, Superman and Captain America often carry expensive price tags that rival those seen in fine art, and are exponentially higher than their original cover prices. Depending on the title and its age, such issues can fetch thousands or even millions of dollars.
Boosted by a steady diet of comic-inspired movies and television shows about costumed superheroes (mainly those based on characters from publishing powerhouses Marvel and DC Comics), savvy investors in collectible comic books can see a sizable return on their original investment — provided the merchandise is in good condition, and the seller knows what he's doing.
That dynamic was evident recently at the Austin Convention Center in Texas, where fans, buyers and sellers assembled for the annual Wizard World Austin Comic Convention. Austin Comic Con, a smaller and more relaxed affair than its big city cohorts in San Diego and New York City, still featured lots of comics, art and other paraphernalia. It also had its fair share of comic book dealers who offered a glimpse of a market that remains red hot.
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Commack, New York, native Robert Storms told CNBC he attends about 20 shows each year to help drive customers to his online business, which accounts for about 70 percent of his sales. Storms believes that collectible comics can be a sound investment, but cautions against investing without thorough knowledge of the market and current trends.
"Buyers really need to understand their objectives before investing in comics," said Storms.
"Are they buying because they're serious collectors who really appreciate the product, or are they trying to make a quick buck? What's driving demand for the book they're looking to buy, and is that demand sustainable? What condition is the book in?" he asked. "Every book will ultimately reach a plateau, so trends are important."
Storms, who once sold a mint 1963 copy of Marvel's Avengers No. 1 for $250,000, added that his client base is increasingly international, given the booming trend of superhero movies and TV shows.
Big- and small-screen adaptations are "definitely helping to bring in younger buyers, and priming demand in international markets, too," he told CNBC. "I sell a lot of books online to buyers in Europe, the U.K., Canada, Australia, even the Middle East."
'Makes sense ... if you know what you're doing'
All of which means some current and former comic book lovers could be sitting on a gold mine that could easily pay off a mortgage and put their children through school, with plenty to spare.
A copy of Batman No. 1 has a market price of $634,000, while Detective Comics No. 27 — the first-ever appearance of the Dark Knight, which sold for 10 cents in 1939 — is worth at least $1 million. Meanwhile, Superman No. 1 actually sold for a whopping $3.2 million last year, and currently has an asking price on a leading comic website for $4.5 million.
Despite strong demand, buying and selling rare comics may not be for everyone.
"Investing in comics only makes sense if you know what you're doing, [because] 99 percent of comics have no real value to investors," local dealer Brandon Zuern of Austin Books & Comics, who advises friends on collecting with the objective of turning a profit, told CNBC.
He added that one of the current hot trends in collecting is "Harley Quinn," a popular character from the Batman universe best known as The Joker's girlfriend, who is also getting top billing in next August's "Suicide Squad" movie. Quinn's first appearance in 1993's The Batman Adventures No. 12 is now selling for more than $1,000. Zuern added that that "is amazing because just a few years ago, these issues were gathering dust in bargain bins."
Robert Storms
For those seeking to assess the value of their collectibles, one potential resource is the Florida-based Certifiable Guaranty Co., where husband-and-wife team of Scott and Molly Davis help to "[take] the guesswork out of buying and selling."
Molly Davis said that "collectors accept our grade as official, and that's enormously helpful because no one wants to feel like they overpaid or undersold."
CGC-graded books, which are enclosed in a semi-sealed case of inert plastic, tend to be more expensive than identical, non-graded comics, but that's the price many collectors, including investors, are willing to pay for an official grade. In addition to the plastic security case, each CGC-graded book is permanently included in their database with a unique zebra-code that lets investors validate the book's authenticity and official grade. CGC also offers investors the ability to track a book's value over time before or after purchase — similar to a stockbroker watching a stock.
So just how frothy is the market? "It does get a little crazy sometimes," Scott Davis said, due in large part to the proliferation of comic movies and TV shows. Collectors often "submit a comic book with that character's first appearance to us for grading, and try to be the first to people to get it on eBay," he said.
"It's a good strategy, but risky … there's a pretty small window for success," Davis added.
Though it's unlikely comic books will replace blue chip stocks such as Apple or Goldman Sachs as investments, dealers say the market for comic books can create solid returns — as long as the investor fully understands the market dynamics. One dealer highlighted an unusual reason why fundamentals support higher prices.
"It all comes down to moms," the dealer, who asked not to be identified, told CNBC. "If moms hadn't thrown out so many comic book collections when their sons went off to college or left home to get married, then most of us probably even wouldn't be here!"