GAG Immobilien AG is a Germany based provider of real-estate services and consultation in the city of Cologne. The company operates as a landlord, and is focused on the business of Leasing, Selling and Managing properties. In the leasing business, the company focuses on leasing the properties it owns. The organization apart from being involved in the provision of leasing services, also sells homes, condominiums, flats and buildings. In the Managing business, the entity undertakes the management and administration of third-party apartments for their owners or owner associations.