The most active players on the buying front were private players, who were responsible for almost three-quarters of all the deals that closed in 2009. Most of those investors were small and local shops, and many of them completed single transactions. Among the most active buyers last year were Behringer Harvard, with 10 new assets worth $483.1 million, and Inland Real Estate Group, with seven deals worth $190.2 million, according to RCA. (Inland has its 2009 acquisition volume for Inland American Real Estate Trust Inc. at 9 assets totaling $201 million.) Some public REITs were also in the market, particularly AvalonBay Communities and Equity Residential. They were the seventh and 10th most active buyers by dollar volume, respectively, having spent $146.4 million on three properties and $127.7 on two assets last year.

Private REITs came in second in terms of activity by a group, accounting for 6% of all multifamily acquisitions. They primarily went after core or traditional deals, avoiding the distressed situations.

At 4%, foreign investors account for a larger-than-usual share of the acquisitions activity. Behringer Harvard's partnership with Netherlands-based institution PGGM has upped its deal volume—PGGM alone was the second-largest buyer last year, spending $307.5 million on six properties—and the joint venture of UDR and Kuwait is just one of several players observers believe will be snapping up properties on an increasing basis. Foreign investors were also involved in 11% of the distressed apartment sales that occurred, with Canadian and Israeli groups primarily eyeing failed condo projects.