Buyers must prioritize Payload Capacity, which defines the maximum weight the robot can handle, and Reach/Work Envelope, ensuring the arm can cover the necessary workspace. Additionally, Repeatability and Accuracy (typically measured in millimeters, e.g., ±0.02mm) are critical for precision tasks like electronics assembly. You should also verify the Degrees of Freedom (Axes); while 6-axis robots offer maximum flexibility, 4-axis SCARA robots may be more cost-effective for high-speed pick-and-place operations.