Not so long ago, developers focused their energies on building expansive condos for Wall Street executives and trust funders, corporate lawyers and movie stars, stuffing them full of Bosch and Viking and Miele, en-suite marble baths and heated herringbone floors. Now it seems like the only buyers they care about potash magnates, casino kings and Eastern European oligarchs.

At least, what else is one to think given the news of yet another massive single-family mansion—urban castle? chauteau-ette? attached manor home?— planned for West 21st Street. Buzz Buzz Home reports that Skyway Development Group is planning a seven story single family home at 34 West 21st Street, next to the Flatiron District office building that it paid $38.5 million for in June. We guess gentrified neighborhoods really are threatened by aristocratization!

The planned mansion is slated to rise above a ground-floor retail space (not a Denny’s, we hope!) on the second through seventh floors of the 57,824-square-foot building. Perhaps Skyway was inspired by the biggest sale of the year—the “loft-mansion” at 144 Duane? After all, if you have hundreds of millions of dollars why not buy an entire building to store your impressive furniture and art collections, and on occasion, yourself?

And to think! Just last year the Whitman, a four-unit luxury condo on Madison Square Park, seemed lavish, with a 6,540-square foot duplex penthouse that came with 3,000 square feet of terraces, air rights and a $22.5 million price tag. The building attracted rich people like Chelsea Clinton and Jeff Gordon, who were looking to pay $10 million or so for a few thousand super luxurious square feet. People who would not immediately think “mine!” upon seeing a 50,000 or 60,000 square foot building. Oh, how times have changed!

The price for the Flatiron residence has not yet been decided, though the going rate for similar trophies is $100 million plus. Or at least, that’s the going ask. Never mind that no property, no matter how magnificent, has come within $10 million of it. That doesn’t stop sellers from asking! There’s River House, with its $130 million mansion co-op, a price that doesn’t even include the work needed to actually covert the 62,000-sqaure foot space into a home. At least the $125 million Pierre penthouse is move-in ready. And who could ignore the $115 million townhouse at 12 East 69th Street, which hit the market in late December wrapped in a giant red bow? Or Stephen Cohen’s fire sale Beacon Court penthouse, with its price dropped to $98 million (He has to pay the SEC’s billion dollar fine somehow!). Just today, the penthouse at the Sherry Netherland got a set of new brokers and went back to the $95 million ask that it’s been failing to get for the past year.

Meanwhile, One57 and 432 Park and all the other 57th Street skyscrapers are falling all over themselves to win the hearts and wallets of hedge fund managers, foreign investors and basically anyone else whose vast resources go far beyond what most rich people will see in a lifetime.

Then again, who didn’t see this coming? First the upper middle class left, clutching their Frappucinos as they drove away in the Mini Coopers they couldn’t afford to park in a good garage anymore. Now the millionaires have all decamped to Brooklyn and it won’t be long before New Yorkers with live-in chefs and multiple wood-burning fireplaces start reminiscing about the days when non-billionaires could actually afford to live in Manhattan.