Plenty of billionaires buy a mansion in Miami. Ken Griffin seems to be buying the parts list for a city.

The Citadel founder, whose fortune Forbes pegs at about $60 billion, already controls most of a block in the financial district, a seven-lot spread on Star Island and a private dock for his 308-foot yacht. On Sept. 30, he added a college campus.

Griffin closed on roughly 30 acres of Wynwood for $1.1 billion in cash, a purchase the seller’s company billed as the biggest land assemblage Florida has ever seen. That same day, Carnegie Mellon University said he was giving it $3 billion, which the school calls the largest gift an individual has ever made to higher education. Two-thirds of that money is earmarked for a Miami outpost on the site, planned for more than 3,500 students and nearly 300 faculty. Construction is slated for 2027, with the first students due in 2028.

One source likened his continuing investments in Miami as “a man building his own city within a city.” 

Griffin himself is not underselling it.

“The opportunity to bring one of the greatest universities in the United States of America to Miami will change the very fabric of this city for centuries to come,” he said in public comments last week. “This may be the most impactful investment I will make in my lifetime — both for Miami and for our nation.”

So is one man stitching together his own town inside the Magic City?

Some brokers wince at the label.

“I think building his own city is kind of a provocative way of putting it,” Douglas Elliman broker Devin Kay told The Post. “But when you look at the scale of what’s happening, you understand why people are kind of phrasing it that way.”

Corcoran’s Mick Duchon offered a gentler version.

“It’s not that he’s building a city within a city, but he’s helping the city evolve and creating depth,” he said.

The Monopoly board

The receipts back up the hype. In Brickell, Griffin paid $363 million in 2022 for a 2.5-acre bayfront lot where a 54-story Citadel headquarters is planned. He spent another $286.5 million on the office tower next door, bought out every unit in a neighboring 22-story condo building he intends to raze and added 300 apartments to the blueprint. In July, the city agreed to sell him a historic cottage for about $3 million, the last holdout on the block.

A few miles north, he teamed with Goldman Properties in January to buy the 545wyn office building for roughly $180 million. Then came the Wynwood land from developer Moishe Mana, who has said he spent about $70 million piecing together his holdings there starting in 2009.

Then there is where Griffin sleeps. He paid $106.9 million in 2022 for a Coconut Grove estate, the first Miami home to crack nine figures. His Star Island lots ran about $169 million. And because a boat that size needs parking, he won approval for a private marina on Terminal Island, where a proposed helipad has nearby condo owners up in arms over noise.

Brokers say the shopping list matters less than what it adds up to.

“Griffin isn’t just simply buying Miami real estate, he’s investing in the infrastructure of a city, whether that be business, education, housing, and talent,” Kay said.

The school plugs a hole that has long dogged the city’s corporate ambitions, according to Duchon.

“Part of the reason some larger corporations historically haven’t moved their headquarters to Miami is because of the talent pool,” he said, adding that Griffin is “baking in future growth” and “bringing permanence to the market.”

Kay said the money that flooded in during the pandemic now has reasons to stay put, since “the infrastructure is being built around that wealth.”

For Lourdes Alatriste, a Douglas Elliman agent who came to Miami young, the shift is hard to overstate. She recalled the drug-money years of the 1970s and ’80s, then the ’90s wave of models and A-listers.

“We had all those celebrities coming in for a second home, never to stay full time,” she said.

Now the buyers stay year-round, and she credits Griffin, whom she has met, with setting the pace.

“He doesn’t hesitate. He moves and gets it done,” Alatriste said. “I think he is one of the biggest assets we have here right now.”

She expects Wynwood, long a district of murals and bars, to follow the path of a far tonier neighbor.

“I see it transforming like what Coconut Grove was many, many, many years ago,” she said, before adding a caveat. “It needs more walkability.”

Follow the leader

Where Griffin goes, other fortunes tend to trail.

“He came in, Jeff Bezos came in, Larry Page came in,” Alatriste said.

Kay traced the luxury boom to Griffin’s early bets, calling him “the first one to raise the bar in South Florida” and noting that “all the other smart money follows.”

The sales job has gotten easier, too.

“We’re not pitching Miami anymore. Miami speaks for itself,” Duchon said.

Not everyone gets a seat at the table. Kay said homes priced at $10 million and up have soared, while buyers a rung or two below are getting squeezed.

“A lot of people that are in the one to five million dollar price point have gotten priced out of a lot of these markets because it’s just gotten way too expensive,” he said, adding that many are being “edged out by cash buyers.”

“With more people moving here than there are properties to even sell them, that’s putting pressure on pricing and pricing a lot of people out of the market,” Kay said.

Some of his own clients have started shopping outside Miami and Palm Beach altogether, he added.

There are other reasons for caution. The campus is years from opening, and no one has yet produced numbers showing it has moved home prices. Griffin’s record here isn’t spotless, either. He paid $60 million for two Faena House penthouses in 2015 and later unloaded them at a $13.8 million loss.

His cheerleaders are already sold.

“He has touched things that nobody else had touched,” Alatriste said.