I agree that the replacement window business is confusing. What I did was to ask each potential vendor if the windows were rated by the NFRC. NFRC is a group that tests windows and then posts the results to allow the consumer to compare the windows side by side. Please note to get the exact listing as the NFRC will likely show MANY windows for some manufacturers. Some vendors are not listed on the NFRC but that does not necessarily mean their windows are junk. I found the best tool was the NFRC but that is not the ONLY tool. NFRC can be found at http://www.nfrc.org

As far as contractors, I had the finalists submit me a list of customers. I called each and every one. I had the contractor provide me with what they installed at each home and then asked the homeowner what they had installed to verify that they both said the same thing. I also called the BBB and the local remodelers association. The installation on my windows starts next week. I guess I’ll see if I did enough background checking……