In the automotive design field, digital modeling tools play a critical role in the early phases of vehicle development. This study explores the sustainability and efficiency of five 3D modeling software tools, Blender, Rhino, Alias, Creo, and Gravity Sketch, widely used in concept design, but highly heterogeneous in terms of mathematical foundation, cost, and user interaction. A comparative analysis was conducted through two case studies: the first focused on a detailed front-end design, while the second involved the modeling of a full car body in conceptual form. All surfaces were developed using Subdivision Surface (SubD) modeling techniques to ensure mathematical consistency and fair comparison across platforms. Five users with varying experience levels contributed to the evaluation, ensuring a balance between modeling depth and critical validation. Key performance indicators included modeling time, surface quality, usability, hardware requirements, and licensing cost, with particular attention to economic and environmental sustainability. Notably, the adoption of open-source or VR-based tools (Blender and Gravity Sketch) highlighted reduced resource consumption and lower barriers to access, offering viable alternatives to high-cost proprietary software. The findings suggest that tool selection in concept design should be strategically aligned with project constraints and sustainability goals. This work provides practical guidelines for designers, researchers, and startups seeking cost-effective and environmentally responsible approaches to digital modeling in automotive design.