Many people you will come across will be "Authorized or Authorized Dealers" for these companies but not "Certified Installers"
So what's the difference and why do you care?
To become "Authorized" all a company has to do is make out a dealer application to sell the product.
"CERTIFIED INSTALLER" applies to one who has spent a great deal of time and resources to take various factory training on specific products to learn how to DESIGN, INSTALL, SERVICE, and MAINTAIN the systems.
Take a look at the certificates.
Below is a list of current factory Certifications.