factor. If your doing this for energy efficiency the pay back for high efficiency windows is terrible. With some taking almost 60+ years to get your monies worth in savings. If your doing this for looks, as your old perhaps are dirty and your tired of painting then look at the quality of construction.

Your Anderson windows will always have parts available such as latches, spring balances, screens and such. The Jeld Wen, not so sure about those.

Most of the windows constructed these days are pretty good. With exception of the low end builders grade types. So choosing between store brands from Lowe's or Home Depot your not going to find much difference between their window lines. Once you break into the Anderson, or Pella types then you need to do your homework more carefully as though both are real good manufactures, its the installation teams that make up the difference between them. And if you go this route, I would work directly with their stores then go through the big box store sales people.

So look at energy efficiency.

Then look at repair part availability. They will tell you no problem getting parts for the Jeld Wen, but how long have they been around? Anderson has been around for many years and will continue to be so. Same goes with the Craftsman as well.

Then look at installer quality. You can have the best window made, but if its not properly installed, flashed and caulked it is worthless. It will fail and leak air. So get references on whoever is putting them in.

Be sure that they have their lead paint renovators license. If not, do not use them. They are required by law to provide you with a lead paint pamphlet explaining the law to you and what they are required to do to keep your home lead paint safe.

Certainteed and Jacobson products in Tampa..Jacobson has a couple of manufacturing shops there...maybe call and see if they are near you! Good Stuff priced Right! JL

To add to what Belle and Yamini said, don't just ask if they have a license, ask to see the license and the workers comp certificate or exemption card.

Then go to myfloridalicense.com and check.

If the contractor is licensed, he/she has to be insured and bonded to keep their license active.

Make sure the license starts out with CCC or RR other wise the license they have is probably a handymans license, which is ok if all you need done is painting or pressure washing.

Good Luck