Billionaire and ousted WeWork CEO Adam Neumann was searching for a trophy $50 million-plus apartment on Fifth Avenue before the company’s disastrous IPO effort — but a source says he was bluntly rejected by the co-op boards of a number of prestigious buildings after media reports of his erratic behavior.

Neumann and wife, Rebekah, were shopping on Fifth for an apartment, aiming to reside among the city’s wealthy elite. But, according to a well-placed real estate insider, he was shocked that the co-op boards of at least three fancy buildings, including 950 and 960 Fifth Ave., responded, “He need not even apply.”

Neumann has hired multiple brokers in the past and most recently unleashed WeWork’s former head of commercial real estate Mark Lapidus on the search. The insider said, “Neumann wanted the gilded life on Fifth Avenue … But the brokers put in discreet calls to members of the co-op boards, and they all said no.” According to the source, Lapidus even said to one agent, “Adam Neumann is going to be the first trillionaire of all time — any building would want him.”

Neumann stepped down as CEO last week in the wake of his alleged outlandishness. While he reportedly wanted to build a WeWork on Mars, he also said at a company event in 2018 that he wanted to solve a worldwide problem by giving orphans “a new family: the WeWork family.” He also banned staffers from expensing meals that included meat. And employees said Neumann seemed to manage by his own code of conduct.

Before WeWork delayed its IPO, Neumann had cashed out more than $700 million from the company and had been buying up homes with abandon, The Post reported.

A rep for Neumann and Lapidus said, “This story is completely false,” adding, “Mark walked into those buildings as a favor to a broker and left within five minutes. There was never any thought of the Neumanns living there, nor a discussion with anybody about them applying.”