Both sides of the issue hired law firms, lobbyists, and business associates to promote their positions to city and state officials. A report by the Center City District said if both One Pennsylvania Plaza and the Cira Centre, another skyscraper in the KOZ controversy, were filled by corporations moving from other Center City office towers, the city could lose US$153 million by 2018. A report released by the group of building owners opposed to KOZ says the two buildings could cost the city almost US$91 million a year. In contrast, a report issued by a consulting company hired by Liberty Property Trust said that a KOZ designation for the skyscraper could generate US$27 million for the city. Critics of the KOZ designation also claimed that close relationships between Liberty Property Trust and Comcast and the Rendell administration were inappropriately influencing the governor's position on the issue. When Rendell was mayor of Philadelphia, David L. Cohen, a Comcast executive vice president, was Rendell's chief of staff, and William P. Hankowsky, Liberty Property Trust's chief executive, was director of Philadelphia's development agency. Rendell dismissed the claims, saying "Every building owner in town was a contributor to me."