ROCKFORD, ILL. — Quantum Real Estate Advisors Inc. has arranged the sale of an 82,500-square-foot property occupied by grocer Schnucks in Rockford for an undisclosed price. Originally built in the 1950s, the net-leased building at 2642 Charles St. has undergone a full renovation. Dan Waszak and Brett Berlin of Quantum represented the seller, a developer based in California. The buyer was a private, institutional investor based in California.