Vehicle body damage caused by accidents often presents unique conditions, making it difficult to acquire practical maintenance skills through textbook theory alone. To address this issue, this study explores body repair techniques, including the complete replacement, partial replacement, and modification of side quarter panels, with a focus on preventing depreciation, reducing environmental pollution, and maximizing vehicle owner satisfaction. In particular, the study highlights the need for a standardized body repair manual for vehicles with severe damage to the rear side members caused by rear-end collisions. This manual aims to minimize repair discrepancies due to differences in operator skill levels and proposes a solution to prevent the depreciation of vehicle market value after repairs. The study’s objective is to standardize the repair and replacement of rear side members in vehicle repair shops, ensuring consistent repair quality for consumers and contributing to the preservation of vehicle value.