The genius of Tony Stark and his company has brought him unimaginable wealth and fame, but despite his charisma and status, Namor has proven to be much richer than him. Though much of Namor's wealth is a secret to the characters in the Marvel Universe, it's not shocking to see that he has access to money and riches that rival Iron Man himself. As the ruler of all the world's oceans, Namor is overwhelmingly rich in resources, even before a nifty trick that makes it so he rarely has to use them.
Being a king of the ocean has its benefits, and Namor is the (mostly) unquestioned ruler of a planet-spanning, technologically advanced civilization. While Tony's genius and family wealth mean he's rarely totally without resources, he's lost his personal fortune multiple times and had to build it up again, whereas Namor's wealth is far more diverse and harder to squander.
Namor's wealth starts with his rulership over his kingdom, which has riches specific to the people of the ocean, but it doesn't end there. Considered part of his territory, the entire ocean offers lost treasures and money from sunken ships and lost artifacts. With his people often combing the ocean floor for these treasures, Namor sells or trades what they find. With that money he was able to create a company all his own: Oracle Inc. The first appearance of Oracle Inc. was in Namor, The Sub-Mariner #1 by John Byrne, Bob Wiacek, Glynis Oliver, and Ken Lopez. It was there that Namor decided to use his mountain of treasure to advance his power on the surface world by using humans as a front for the business, allowing him to become one of the richest individuals in the Marvel Universe.
Namor Commands the Wealth of a Nation
Oracle Inc. was immensely successful, given its near-limitless funding. Once Namor bought the company, the stock rose and public interest in the company rose alongside it.In Namor, The Sub-Mariner #2 it was shown that the company became direct competition to some of the world's leading corporations, causing suspicion within evil corporations like Roxxon. At this point, Namor had access to every piece of treasure lost to the sea over hundreds of years of human history, a nation's natural resources, and a successful company.
While Oracle Inc. is the most prominent example of how he's used his wealth on the surface, it's important to note that his wealth doesn't stop there. Namor has multiple famous businesses - he even funded a movie about the Fantastic Four - and holds dominion over a society which has its own inventors, geniuses, and even mystics. Tony Stark is a genius businessman whose unique inventions afford him a huge amount of financial power, but even his overflowing coffers are dwarfed by figures like Namor and Black Panther, who command entire nations with unique resources to offer the world. While there have been times when Tony Stark has been so down on his luck he's had to turn to people like Thor and Deadpool to fund the Avengers, as long as he possesses the throne of Atlantis, Namor is a whole other level of financial powerhouse.