Tom Edson’s lawsuit against real estate broker David Horwich alleged Edson paid $600,000 for commercial space in the Plaza on DeWitt condominium building, 260 E. Chestnut St., Chicago, based on a listing drafted by Horwich that said the vacant unit was the “former location of Stop & Shop Grocery” and was “perfect for grocery, medical clinic, fitness center, restaurant/bar, office.”Although the Chicago zoning map portrays Plaza on DeWitt as being zoned for residential use, Horwich …