The 107 chassis has a known defect in how the front subframe attaches to the body; it can crack and, in the worst case, fall out. Mercedes offered a four-piece kit that is welded on to prevent it, and knowledgeable owners and parts sellers treat the reinforcement as an essential job to confirm or perform.
Front subframe mounting defect and welded reinforcement kit
Mercedes-Benz SLC (C107) · mechanical