Brooklyn house sells for nearly $3K per sq. foot

Nowadays, it costs a king's ransom to buy property in Kings County, and a recent sale proved it.

Brooklyn, one of New York City's hottest property markets, recently saw a 19th century carriage house at 36 Strong Place sell for $5.8 million, according to the NYC Department of Finance's database.

The property, located in the upscale Cobble Hill area of Brooklyn, is listed by real estate firm Douglas Elliman. Based on a price of nearly $6 million and a square foot size of 2000, the Strong Place sale breaks down to $2900 per square foot. On a purely square footage basis, that would appear to put the property's sale in record territory for Brooklyn—and multiples higher than prevailing rates in the region.

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In response to an inquiry from CNBC, Alexander Maroni—the Douglas Elliman broker who closed the sale—told CNBC that the sale was "a testament to the strength of the Brooklyn market. In some cases Cobble Hill is being seen as more attractive to buyers than Brooklyn Heights."

Data from Zillow and Trulia show that the median home value for Brooklyn is well above $600,000, while the average listing price for all properties in the borough is just above $1 million. For context, that is far above the national median home price of $183,000, Zillow data shows.

For all of Brooklyn, the average price per square footage is more than $600. On a scale of 1-10, Zillow ranks Brooklyn's market as a 9.1, or "very healthy."

Brooklyn has become a microcosm of the frenzied New York real estate market, which some have argued is in bubble territory. Collective property values were recently assessed at more than $1 trillion and Manhattan real estate hit price records last year.

While its square footage price may be impressive, the sale price of 36 Strong is dwarfed by other recent listings in the neighborhood. Last year, a 17,500 square foot brownstone in Brooklyn Heights was listed at a record $40 million, while a 10,000 square foot townhouse in nearby Cobble Hill set a record for the most expensive sale in the borough, at $15.5 million.