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. Homeowner stated there was frost build up on one of the lines. After verifying proper airflow, I checked refrigerant levels and found the system to be low on charge. Added 2lbs and 14.75oz to the system. Also added leak sealer, this will only act as a bandaid and is not a permanent solution. Also found the motor starter to be heavily damaged, replaced part to prevent against any major failure of the system. Lastly installed a start assist kit to protect the compressor. All other recommendations declined at this time.