I trusted this contractor and he came and installed a new Humidifier. He did not provide me with receipt or manual. (so that I can register my product and secure company warranty coverage) which from Online research. He uses this tactic so that you are tied and dependent on him. I followed up with this individual but does not respond. He is looking for annual fixed contracts and generate revenue stream, overcharges for visits. HVAC is necessary service so uses his skills to exploit clients. Will never recommend this person.