This real estate market is about to crash

The tallest residential structure in the Western Hemisphere sits at 432 Park Avenue in New York City.

Standing at nearly 1,400 feet, there are 141 apartments for sale in this building, where the average selling price is $21 million, 10 times the price of an "average" Manhattan apartment. A representative for the building said it is over 70 percent sold, though only a few dozen of those sales have closed so far. A recent report in Real Deal indicated that there are anecdotal signs that "sales have plateaued" in the building, including the fact that the developers are dividing some of the full-floor apartments into smaller units to reach buyers interested in a lower price point and boost sales.

New York real-estate prices have recovered with a vengeance in the past year but buyers may be starting to reach their limit.

423 Park Avenue in New York.
Adam Jeffery | CNBC
423 Park Avenue in New York.

The average apartment price in Manhattan hit a record $1.95 million in the fourth quarter of 2015, according to real-estate firm Douglas Elliman. But brokers reported a distinct shift as 2016 began and the data reflect that: The numbers of contracts signed in January and February fell more than 20 percent from a year earlier to their lowest levels since 2009, according to real-estate analytics firm

And expensive apartments are sitting idle for roughly 90 days before being sold, the longest "time on market" since January of 2013, according to the StreetEasy Blog, which tracks New York real estate.

To be clear, the slowdown isn't just in New York: Nationwide, existing-home sales were down 7.1 percent in February, according to the National Association of Realtors. And, while new-home sales overall rose in February, according to the Commerce Department, the gains were confined to one region — the West. Sales fell in the Northeast, Midwest and South, with the Northeast down a whopping 18 percent.

Beyond hard numbers, the late Ed Hart, a credit-market analyst with whom I worked at Financial News Network, taught me the very high value of anecdotal information almost three decades ago. For instance, just before the savings & loan bubble burst in the 1980s, Ed told me that if you see a lot of antique furniture and art work inside an S&L, short the stock!

To him, it meant that depositor money was being ill used and the institution was bound for insolvency.

On more than one occasion, I witnessed such excesses, only to see the offending lender wind up in receivership a mere few months later.

During the Boston condo glut of the late 1980s, Ed Hart counted cranes.

In New York today, the Manhattan skyline absolutely filled with construction cranes, something we haven't seen in this town for quite some time. Real Estate Weekly notes that 70 cranes dotted the Manhattan market in 2015, twice as many as the year before, and almost seven times the number of cranes currently working in Los Angeles. They are mostly devoted to high-end condos.

In addition, some 5,377 new high-end condos units are being constructed at a time when DNA Info adds that foreign buyers are either backing away from New York purchases, or buying cheaper residences, thanks to the strength of the dollar, which makes expensive New York apartments that much pricier.

Foreign buyers have accounted for anywhere from 15 percent of total New York City purchases, to as much as 40 percent of Manhattan's high-priced buys in recent years, real estate expert Jonathan Miller told DNA Info.

The U.S. Treasury Department's recent mandate that the identity of foreign buyers be made known, for purchases above $3 million, could be discouraging overseas investors from buying pricey real estate. And that could have a dramatic impact on sales going forward.

432 Park Avenue is only one of as many as a dozen residential and commercial buildings that will compete for the "tallest" moniker in New York in the next several years.

It's worth noting that, the erection of a region's tallest building has, since the early 1900s, been associated with both stock- and real-estate market tops. Consider these:

The Woolworth building in 1907; the groundbreaking on the Chrysler and Empire State buildings in the late 1920s; the World Trade Center in the early 1970s, along with the Sears Tower in Chicago; the Petronas Towers in Malaysia in 1997, the Burj Khalifa in Dubai in recent years, and the Shanghai World Financial Center in 1998. Every last one of them correlated closely with stock and real-estate market peaks.

Despite the rosy view of builders, there is a serious risk, in my view, that the supply of (mostly) expensive new housing in New York may outstrip demand for some years to come.

Add to that a potential glut of commercial real estate as well. Never in my career have I heard of capitalization rates falling below 3 percent, even in Manhattan. "Cap rates" are a way of valuing commercial real estate. The lower the cap rate, the richer the valuation.

One prominent hotel operator recently confided to me that some 20,000 hotel rooms are being added in New York City, just as occupancy rates are beginning to edge lower, reinforcing the notion that the "tourist trade" in real estate may well be coming to an end.

It's ironic that New York City largely escaped the property bust that engulfed the world in 2008, despite being the very epicenter of the mortgage credit crisis.

For Manhattan, the after-shock of a national real-estate crash may be worse than the earthquake that rocked the nation itself.

If you see steep discounts at the city's tallest buildings anytime soon, you may still not be able to afford a multi-million dollar apartment, but you can make money shorting those entities most exposed to an edifice that is likely about to get wrecked.

Commentary by Ron Insana, a CNBC and MSNBC contributor and the author of four books on Wall Street. Follow him on Twitter @rinsana.

Correction: An earlier version of this article incorrectly stated the sales and closing statistics for 432 Park Avenue in New York City. A representative for the building said 70 percent of the 141 units in the building have been sold and more than 20 units have closed.

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