Hartman Management Inc. has been busy in Houston lately. After purchasing 2909 Hillcroft in late August, the company bought The Preserve at North Loop, a 7-building Class-B office complex that totals 205,046 square feet. The deal closed for an undisclosed amount. The buildings, which range in size from 27,597 to 30,893 square feet, are from 2000 to 2060 North Loop West. Tenants in the complex include Southern Petroleum Co., Transport Workers of America, and several doctors' offices. John Crossin and Julian Kwok represented Hartman Management Inc. in-house, and John Dailey of PM Realty Group represented the seller, Lennar Texas Properties.