The efficiency and validity of product and component reuse should be evaluated in relation to the balance among utility value, environmental load, and cost throughout the entire product life cycle from the viewpoint of society as well as that of individual users. This paper proposes an evaluation method for reuse focusing on this balance from both societal and individual perspectives. In order to evaluate these balances, a multi-agent consumer model representing users with different preferences for products is introduced and an algorithm to ascertain a near-optimal reuse solution is developed. A simplified simulation of reuse is conducted to demonstrate the feasibility of our method.