Columbus Mayor Michael Coleman says he has ordered the Department of Development to investigate the employee who helped a Chinese businesswoman purchase his former Berwick home at an amount that was over market value. Public documents show the employee, Bob Hsieh, also helped Jianhua Li open bank accounts and hire attorneys. Coleman says he did not order the additional assistance and did not know it was offered. The Justice Department is investigating the sale of the home in late 2010 and the help Li received from the city establishing a business in Columbus.