Holders helped me install two state-of-the-art HVAC systems in a century-old mountain ranch house and adjoining guest house that previously were heated only with wood burning stoves and had no AC. It was a complicated, custom project in every sense. The system design was thoughtful and perfectly suited to our needs, and the Holders crew were experienced craftsmen who quickly arrived at practical solutions to unexpected problems. Everyone involved in the project was a pleasure to do business with. I look forward to working on other projects with Holders in the future.