This study proposes an upgradable product design method that falls under the category of “environmentally conscious” product design methods. The method enhances the product’s performance by exchanging or adding only a few of its components. In addition, the proposed method reduces the usage as well as wastage of resources by preventing the disposal of the product itself. This study primarily focuses on manufacturer profit, which was presented as an ill-argued topic in a previous study on upgradable product design methods that potentially provide enhanced sales strategies for upgradable products with an underlying consideration of company sustainability. Moreover, the proposed method in this study assesses how design information uncertainties associated with future prediction (as a ranged value) apply to the concept of set-based design to ultimately obtain ranged sets of design solutions and sales strategies that satisfactorily meet profit, environmental, and functional requirements. Finally, the proposed method obtains ranged design solutions that can realize low environmental loads, low product price, and a highly profitable upgradable product via exclusive application to a multifunctional laser printer scenario. The results of this study indicate the effectiveness of such an upgradable product design method as a vital approach in building a sustainable society.