When purchasing a used vessel, the most critical factor is the Physical Condition and Maintenance History. Buyers must review the Classification Society records (e.g., ABS, DNV, LR) to check for outstanding 'recommendations' or 'conditions of class.' It is essential to conduct a Pre-purchase Inspection (PPI) focusing on hull thickness (ultrasonic testing), the condition of the main engine and auxiliary generators, and the functionality of cargo handling gear (cranes or pumps). Ensure the vessel has undergone its Special Survey recently to avoid immediate dry-docking costs.