You'll be spending a great amount of time and energy on the installation of double glazed windows, and it can also have a great impact on your heating bills. So when you are looking for a double glazing installer, you will want to choose a good one. You need to keep yourself informed to avoid choosing a company that offers poor quality products, unprofessional customer service and no means of redress in the event of any problems. The reputation of your chosen double glazing supplier is important - do neighbours who have used them speak positively?
Price is another key factor, but bear in mind that you generally get what you pay for, with an extremely low outlay generally buying you only a very poor quality product. But you also shouldn't be charged too much, with some companies artificially inflating prices so that they can be brought down during negotiations with you. Companies can do this to give you the impression that you are getting a great deal, when you are actually still paying an average market price.
You should also always ask for no less than three estimates before you sign a contract, also making sure that they are itemised so that you know exactly what you're getting for your money. You should also take note of the company's customer service as soon as you get in touch - for example, do they return your phone calls and messages quickly? Some firms work rather less hard to earn your custom, sometimes not even having office employees. It's also a good idea to ensure that your chosen double glazing installer is connected to a good professional organisation or two, with the Fenestration Self-Assessment Scheme (FENSA) and Glass and Glazing Federation (GGF) among the names to look out for.