I performed a single system cooling maintenance. This is a 2013 zoned gas system. I checked amps, capacitors, filters, electrical, drains, safeties, and cleanliness. I discovered that the return is not sealed properly using cardboard with no sealant. The blower motor is leaking oil and the blower wheel is dirty. The capacitor for the blower is beginning to get low, but it is still in range. Customer did not want pricing on the return sealing. I provided pricing for blower motor replacement with and without cleaning the wheel. I will need to return to wash the outdoor unit.