Offer additional services to boost customer retention.
Get certified to perform AC home energy audits to help customers save money on their energy bills - they will especially appreciate this during the winter months when energy bills rise considerably.
Or why not offer to include air quality assessments, air purifiers, humidifiers, dehumidifiers, and duct cleaning as part of your service? With awareness of indoor air quality on the rise, this service can be of significant value to potential customers and differentiate you from competitors.