When it comes to the richest heroes in the Marvel Universe, the first people that come to mind include Iron Man, Black Panther, and Moon Knight. But, there is one character with a secret amount of wealth that they might never get to enjoy - Wolverine.
Wolverine is one of the X-Men's most powerful heroes, thanks to retractable claws, a healing factor, and an array of other useful powers. Wolverine's mutant powers were upgraded (without his consent) when Weapon X captured and experimented on him, leading to his bones to become pure adamantium. The experiments made Wolverine even stronger, but one of the unforeseen results of being infused with the metal was the fact it actually made him quite valuable... literally.
In Uncanny X-Men #126 by Chris Claremont, John Byrne, Terry Austin, Tom Orzechowski, and Glynis Wein, an exact price range is put on the value of Wolverine's metal bones. In the issue, the X-Men travel to Muir Island to locate some of their teammates after the mysterious Mutant X has wreaked havoc at Moira McTaggert's Mutant Research Center. Wolverine tracks Mutant X's scent but ends up running into a cop. It turns out the cop is Mutant X in disguise, but as he tries to psychically control Wolverine, the mutants metal prevents him from doing so. Wolverine quips that "it ain't just metal, sweetheart. I got a skeleton made of about three million bucks worth of adamantium."
It's practically impossible for Wolverine to cash in on his adamantium bones without seriously mutilating himself by having someone like Magneto ripping him to shreds. Still, the fact Wolverine knows the dollar amount of his adamantium bones is pretty funny. He's secretly a millionaire - but has no real way of cashing out.
Considering Uncanny X-Men #126 was written in 1979, Wolverine's bones are worth quite a bit more today. Adjusted for inflation, $3 million would amount to more than $10 million today. If Wolverine is ever desperate for cash, he can cut a part of his claw off and probably get a decent amount of money for it. Although considering the X-Men's vast resources, he would have to be in a really tight situation financially. But, the option is always there - even if Wolverine selling his own bones for cash would be absolutely horrific for both Logan and readers. There's got to be other ways to make money - especially now that he's on Krakoa.