Yardi Systems said May 17 that it purchased  Ista North America’s Multifamily Services Group, a business that provides utility billing services for owners and managers of apartment complexes. The deal brings 200 employees into Yardi’s fold.

Goleta-based Yardi  makes property management software for apartment complexes. With about 350 employees, it’s one of the largest private employers in Santa Barbara County and one of the largest private companies in the Tri-Counties.

The Ista MSG acquisition brings with it a portfolio of more than 700,000 apartments that use that service, Yardi said in a news release, and will make the Goleta company one of the largest providers of energy management services in theU.S.

The approximately 200 employees in MSG’s three offices, in Alpharetta,Ga.,Jacksonville,Fla., and San Diego, will remain at those locations, Yardi said.

“With these resources and Yardi’s technology roadmap, we are gearing up for significant growth,” Yardi’s executive vice president and chief operating officer, Gordon Morrell, said in a news release.

As competition in the property management software space heats up, Yardi has in recent years gone into acquisition mode and expanded its product portfolio. In August 2011, it bought Dallas-based Multifamily Insurance Group, a provider of insurance services for property managers.  In January, it bought Idaho-based ALMSA Corp., a company that makes electronic health record software for nursing homes and other facilities.

One of its main competitors in the property management space is Appfolio, aSanta Barbara-based startup founded in 2008 and backed by Klaus Schauser,  founder of the business that is now Citrix Online, a division of Citrix Systems.