The present application is directed towards systems and methods for building a living space during construction of a multi-unit housing structure. In particular, the present application describes various embodiments of prefabricated building modules that may be built and equipped with plumbing, HVAC and/or electrical fixtures prior to installation in a multi-unit housing structure. Because modules may be configured prior to installation in a housing structure, the use of prefabricated building modules may increase efficiency of construction and provide enhanced customization over other non-configurable building units.