Performed AC cool check on two systems. Checked electrical, mechanical, safety, and performance of the systems. Guest house system was low on refrigerant. The capacitor on the condenser unit had also failed. No other major issues were found with either system. Drain lines cleared and treated. Condenser coils cleaned. Options for repair were presented to customer and they chose to have the capacitor replaced and the system recharged. Repairs where completed. Systems were running at the time of departure.