Buyers must prioritize the compressor model authenticity, as Bitzer is a premium brand often subject to counterfeiting. Ensure the unit features an original Bitzer semi-hermetic or scroll compressor with a verifiable serial number. Key specs include cooling capacity (kW), evaporating temperature range (low, medium, or high back pressure), and refrigerant compatibility (e.g., R404A, R134a, or R448A). Additionally, check the condenser surface area and fan motor efficiency to ensure the unit meets the required heat rejection standards for your specific climate.