glass doors, which added to the cost because of their size. Mine were simply old and due to helicopter traffic (I was near Dod Med HQ in Falls Church) were literally cracking. To me the benefit was more out of utility, noise reduction (which was much bigger than expected), and monthly savings on heating/cooling (which we saw a result of.)

I did the three bid approach with Long, Pella, and Anderson. I ended up with Long because they really had a good window/door (but honestly they all were good), but I told them all who they were up against and told each one individually no at first to see who would come down in price. Long really dropped in price and got hungry...they sent in a different person (a closer!) and won my business.

In selling my house two years ago, the windows and doors never came up. It was just lumped into all of the other improvements I made to the house since buying it. Moral of story here is that I wouldn't consider them for resale value, but only for the benefits I listed above and how long the plan is to stay in the house.