This manuscript addresses the process of private promotion of collective housing buildings that took place in the early decades of the second half of the 20th century in the city of São Paulo, Brazil, highlighting the role of the real estate market. Its main objective is to analyse the changes and adaptations of modern ideas led by the São Paulo real estate market and how they influenced the emergence of new housing typologies that remain current to this day. The COPAN Building, designed by architect Oscar Niemeyer following a commission from Banco Nacional Imobiliário, was chosen as a case study. Linking the architectural results with the production process, it appears that some concepts conveyed by the Modern movement were fundamental to achieving the new housing typologies.