I bought a voucher for duct cleaning from Sterling Cleaning. They came on time, and were extremely thorough, professional, and knowledgable. I was so impressed with all the extra time and care taken, that I later used them to do carpet and upholstery cleaning, and plan to have them do my windows and eaves in the spring! They are owner operated, with something like 20 yrs of experience, and it shows! Highly, highly recommend them to everyone I know. Check out their website.