Three other buyers have optioned about six more acres and should close their deals in 60 days, Andy Markham of Grubb & Ellis Co.'s Phoenix office tells GlobeSt.com. Meanwhile, brokers have just shuttled off another option contract for one acre to a would-be buyer for a final look-see. "We're getting a lot of strong interest from different size users," he says, careful not to disclose just who is eyeing land for build-to-suit construction.

Markham and Mike Haenel, a Grubb & Ellis senior vice president, represent SunAmerica, based in Century City, CA. Dan Callihan of CB Richard Ellis' Phoenix office negotiated the acquisition on Richard Jensen's behalf.

The SunAmerica business center is located north of the intersection of Arizona Avenue and Warner Road. Markham says the park is a hot item because "there's not a lot of industrial zoned land or product in the area." RX Systems will be joining Piper Plastics, which paved the project's start with a four-acre buy, and Cintas, which took the deed to six acres.