Coldwell Banker United, Realtors was the top residential real estate brokerage in Houston in 2012 by transaction sides (7,644) and dollar volume ($2.01 billion), the Houston Chronicle reports. The fracking boom and medical industries have helped boost the local real estate market, with homes near the “Energy Corridor” on the west side of town seeing big gains, the Houston Chronicle said. The newspaper used Real Trends data to compile a list of the top 100 brokerages in the market. Source: chron.com.