Cash-Back 1.0 presents research on the development of methodologies and technologies to simulate the cause and effect of early stage geometric design alternatives of buildings and the real time results upon financial pro-forma. Through the encoding of design rules and their associative relationships to financial pro-forma the research illustrates enhanced visualisation of early stage building design decisions and their cumulative impact on financial goals and constraints. The research presents value an associative parametric design process affords often-disparate domains through correlation and visualisation. The paper describes incorporation of a feedback loop between pro-forma and geometric models in conjunction with an optimisation method. Given the level of uncertainty in early stage design decision making the research contributes partial solutions to the domain problems of design decision uncertainty and design cycle latency and is further argumentation for increased use of parametric design methods and automation to support design domain integration.