Spencer Schlager and Charles Rosenberg’s CS Ventures bought six Worth Avenue luxury storefronts for $30.3 million. The investment firm bought the 8,500-square-foot retail building at 243 Worth Avenue from Middleburg, Virginia-based Greenstone Realty Advisors, records show. The building, built in 1925, is center stage on the island’s luxury shopping corridor. Its tenants include Versace, Bottega Veneta, fine jewelry shop Maison Maurice, Poupette St Barth, 55 Croisette and Valentina Kova, Schlager confirmed.