It’s always smart to ask for references, especially when you’re hiring contractors to work inside your home. Any reputable company will be happy to provide references, and plenty of them. Also, check out the air duct company’s website and online reviews to find out what people say about their experiences with the company.
You can tell a few things by the length of time a company has been in business, including how experienced and reputable it is. Make sure the company you hire for air duct cleaning has been around long enough to have the experience needed to get the job done correctly.