NYC is hardly built out when Trump can add 2,000 units on a 20,000 square foot lot by going 80 stories high. What the OP is refering to is the General Plan for Carlsbad which designates the areas that are approved for residential development and can only be amended with years of hearings, votes, etc. The last planned development for Carlsbad is Robertson Ranch in the northeastern part of the city. In the south once La Costa Greens and La Costa Ridge sell out there is only one other approved parcel which is for about 50 homes near La Costa Oaks. Obviously restricting supply will help home prices over the long haul. See Del Mar, Solana Beach and Encinitas for verification.