This paper focuses on the use of design compatibility analysis (DCA) to maximize the life-cycle value of mechanical systems. Early stages of design affect various issues that comprise the life-cycle cost of products as well as reliability and serviceability. Our research uses the concept of DCA to model the life-cycle cost and customer value of mechanical systems. DCA focuses on good and bad examples of designs and gives an overall evaluation of designs in a normalized scale. This paper summarizes the methodologies and computer tools develped at the life-cycle engineering lab at Ohio State. Specifically, the paper describes computer programs that evaluate layout designs and give suggestions for improvement.