AC precision tune up. Clean and tune up AC; cleaned condenser coil, checked all outdoor electrical components, tested indoor air flow, checked refrigerant levels, and tested overall AC operation. Found system freezing up. This is due to poor airflow from small return ductwork. Unable to accurately gauge where refrigerant charge is at this point due to airflow issue. I recommend replacement of full system to ensure all airflow is correct and Efficient. Customer would like follow up from office to schedule home advisor appointment due to busy schedule.