Boutique Co-op Property Launches Sales on Upper East Side By BrokerOwner.net October 27, 2020 Real Estate Sales October 27, 2020. Sales have officially launched at 1228 Madison Ave., a boutique-scale luxury residential co-op building developed by CBSK … Share on: Post navigation Previous PostNorthern Colorado Springs real estate sales: July 20-26, 2020 Next PostReal estate tech roundup: Asteroom, Homesnap and SafeShowings