Irving-based AAA Texas plans to move and expand its headquarters to Coppell after buying Gateway Corporate Center I and II, a two-building office campus off Freeport Parkway. Terms of the deal are undisclosed. The property sale is scheduled to close by the end of March. “We wanted to own property instead of leasing,” AAA Texas spokeswoman Linda von Quintus told me Thursday afternoon. “Texas is growing in population and we wanted a property for a large operation and grow in the market.” The buildings at 1225 and 1275 Freeport Pkwy. total about 225,000 square feet. The buildings are valued at $6.4 million and $6.6 million, respectively, according to the Dallas Central Appraisal District.