We first carefully listened to the characteristics of the customer's product range and the sales flow, organized the structure of the issues, and formulated the requirements definition together with the client. Based on that, we designed a selection logic that allows users to narrow down the optimal products according to their usage and conditions, and developed a web application that anyone can use to find products without confusion. The content of the estimates is seamlessly linked to the sales support system, enabling a smooth progression of subsequent sales activities. Furthermore, through the 3D preview function, users can confirm the layout images and dimensions of products, creating an experience that supports customer decision-making. We built a new process that is efficient and satisfying for both sales and customers.