Housing developments (condos and suburban developments) are not necessarily homogeneous. Developers provide di¤erent types of units of various sizes and other characteristics catering to di¤erent types of customers. In this paper, we allow joint production and local consumption externalities within each development, and show that land developers who seek a pro…t-maximizing set of units in developments may provide mixed developments. We show that there exists an equilibrium, and that every equilibrium is Pareto e¢ cient. We provide examples in which mixed developments arise in a long-run equilibrium. We relate this work to a widely used hedonic pricing model by Rosen (1974), and to an equilibrium concept under asymmetric information by Rothschild and Stiglitz (1976).