Chatsworth Business Park has sold for more than $29 million, according to real estate database CoStar Group Inc., a hefty bump-up over its prior purchase price. Laramar Group of Chicago bought 21415, and 21605 to 21615 Plummer St., a total of nearly 232,000 square feet, for $125 a square foot. According to CoStar, LNR Partners of Miami Beach, Fla., paid nearly $21 million, or about $91 a square foot, in November of 2011 for the properties, which means it sold them for a 38 percent gain. Laramar Group is primarily an apartment investor and property manager, and announced earlier this week it opened an office in East Hollywood to support its expanding presence in the L.A. market. The 97,000-square-feet office building at 21415 Plummer was built in 1986, while 21605 to 21615 Plummer was a light manufacturing property built the same year. According to CoStar, Los Angeles County occupies most of the two spaces for social services. Marc Renard and Manfred Schaub of Cushman & Wakefield negotiated the sale on behalf of LNR, according to CoStar.