RICHMOND, TEXAS — California-based brokerage firm RealSource Group has negotiated the $5.8 million sale of a 3,072-square-foot restaurant building in Richmond, a southwestern suburb of Houston. Shake Shack occupies the newly constructed building, which is located within Waterview Town Center, a 134-acre mixed-use development by Read King, on a 15-year, triple-net lease. Austin Blodgett and Jonathan Schiffer of RealSource Group, along with Parasell Inc., represented Read King in the sale. Anthony