For those interested in watching the construction of a multifamily asset portfolio in progress, look no further than Dallas-based Behringer Harvard, which last month announced its acquisition of Acacia on Santa Rosa Creek, a 277-unit multifamily community in Santa Rosa, Calif. The announcement came just two days after Behringer Harvard’s purchase of San Sebastian, a 134-unit age-restricted community in Laguna Woods, Calif. These two deals mark Behringer Harvard’s 20th and 21st acquisition under the company’s Multifamily REIT 1, a publicly-registered, non-traded real estate investment trust with an offering size of $2 billion that has dominated the multifamily deal space for the past year.

Behringer Harvard closed out a banner 2009 with acquisitions of the 177-unit Calypso Lofts in Irvine, Calif., and Gerding Edlen’s 16-story, 352-unit residential tower located in downtown Portland, Ore.

With the firm’s most recent acquisitions, the Behringer Harvard Multifamily REIT now has investments in 5,600 units of multifamily assets across 11 states—and it looks like the firm is just getting started. “I think our run rate on the acquisition side is going to increase dramatically in 2010,” says the firm’s senior vice president Mark Alfieri. “I think we’ll buy twice as much.”

All of Behringer Harvard’s latest deals were made as a joint venture between the company’s Multifamily REIT 1 entity and PGGM, a Dutch pension fund and Behringer Harvard’s primary co-investor. Chris Wood