NEW YORK CITY—Following a year in which it didn't even place in the top 10 locally, the Blackstone Group dominated New York commercial real estate investment during 2015, according to Real Capital Analytics data. The world's largest private real estate investor became the biggest buyer in its own backyard last year, accounting for 21% of Manhattan commercial property transactions by dollar volume.

Bloomberg Business reported Friday that Blackstone, headquartered at 345 Park Ave., bought $9.6 billion of commercial properties locally last year and sold $4.2 billion, mainly in Manhattan. Although its highest-profile acquisition was the 11,000-unit Peter Cooper Village/Stuyvesant Town apartment complex in Midtown South, which it acquired from CWCapital Asset Management for $5.3 billion in partnership with Ivanhoé Cambridge, Blackstone's dealmaking last year ran the gamut of office, hotel and retail assets as well as multifamily.

The Stuy-Town complex, which traded to the Blackstone/Ivanhoé partnership more than five and a half years after its previous owners defaulted on a $3-billion mortgage, was not the only apartment property Blackstone acquired in Manhattan last year. The asset management giant also partnered with Fairstead Capital to buy a 24-building portfolio of mid-sized residential assets located mainly in Chelsea and on the Upper East Side. At $690 million, it was among the largest multifamily deals the borough had seen in recent years until the Stuy-Town mega-sale was arranged.

In the office sector, Blackstone acquired a 50% interest in a nine-property portfolio that RXR Realty had assembled in stages beginning in 2009. The interest in the portfolio, which also included a quartet of assets in Princeton, NJ, sold for a  total value of $4 billion, according to RCA. Largest of the properties by both square footage and dollar volume was the 2.3-million-square-foot Starrett-Lehigh Building at 601 W. 26th St.; other Manhattan properties included 620 Ave. of the Americas, 340 Madison Ave., the office condominium at 1166 Ave. of the Americas and 1330 Ave. of the Americas. Later, Blackstone and RXR would partner on a minority stake in the Helmsley Building at 230 Park Ave.

Last year, Blackstone ventured to the outer boroughs to acquire a retail condo outside Manhattan. It paid $340 million for the 508,000-square-foot retail condo at the Shops at Skyview Center, part of the Sky View Parc complex in the Flushing section of Queens. In the hotel sector, Blackstone picked up the JW Marriott Essex House as part of its privatization of lodging REIT Strategic Hotels & Resorts.

Although it was a net buyer in New York City last year, Blackstone also made news as a seller. In the nation's largest single-building office sale since 2008, the company sold 1095 Ave. of the Americas to its partner on the Stuy-Town deal, Ivanhoé Cambridge, for $2.2 billion. In other transactions, it sold an office property at 717 Fifth Ave. to Anbang Insurance Group, an office condo at the former New York Times headquarters at 229 W. 43rd St. and the leasehold on the London NYC hotel in Midtown.

Ken Caplan, CIO of Blackstone's real estate unit, told Bloomberg on Friday that the company intends to be an active investor in the city this year, as well. "Market volatility will certainly have an impact, but disruptions often present opportunities for those who have capital available to invest," Bloomberg quoted Caplan as saying.