On a June afternoon in 2018, a man named Mickey Barreto checked into the New Yorker Hotel. He was assigned Room 2565, a double-bed accommodation with a view of Midtown Manhattan almost entirely obscured by an exterior wall. For a one-night stay, he paid $200.57.

But he did not check out the next morning. Instead, he made the once-grand hotel his full-time residence for the next five years, without ever paying another cent.

In a city where every inch of real estate is picked over and priced out, and where affordable apartments are among the rarest of commodities, Mr. Barreto had perhaps the best housing deal in New York City history.

Now, that deal could land him in prison.

The story of how Mr. Barreto, a California transplant with a taste for wild conspiracy theories and a sometimes tenuous grip on reality, gained and then lost the rights to Room 2565 might sound implausible — another tale from a man who claims without evidence to be the first cousin, 11 times removed, of Christopher Columbus’s oldest son.

But it’s true.

Whatever his far-fetched beliefs, Mr. Barreto, now 49, was right about one thing: an obscure New York City rent law that provided him with many a New Yorker’s dream.