The Multi-family Districts (R-4, R-5, R-6) and their regulations are established in order to achieve, among others, the following purposes:
(a) To regulate the density and distribution of the population to avoid congestion and maintain adequate services;
(b) To promote the most desirable and beneficial use of the residential land in accordance with the Plan of the City;
(c) To regulate the bulk and location of dwellings in relation to the land, in order to obtain proper light, air, privacy and usable open spaces on each zoning lot appropriate for the district; and,
(d) To enable the development of attached single-family and multi-family dwellings in appropriate locations.