I am a building contractor and for years have watched while customers had windows installed that were marketed to them as being cost-effective - windows that would "save" them "tons" of money in heating costs! This is a blatant lie. As a trained energy auditor, I can tell you the most bang for your buck in terms of saving you money for heating or cooling your home is in INSULATION - ***not* **WINDOWS! That said, if you are desperately in need of new windows, consider buying a moderately priced window like HARVEY. They are very well made and will last as long as some of the higher priced more well-marketed replacement windows. They have various types to choose from, but make sure you have them installed by someone who knows how to INSULATE because the biggest heat/cooling losses are around your windows. Windows are not, in an of themselves, a big energy saver, thus spending tons of money on replacement windows will not save you tons of money. Consider spending a little extra for reflective material on top of the window, but if you are on a restricted budget and can't afford replacement windows at all, try buying an exterior storm window. Exterior storms are often overlooked and can offer you a better cost-to-savings ratio in the long run. If you really want to save the most money and be as green as possible - don't let someone sell you windows. Spend that same money for replacement windows on air sealing and attic insulation. Your return will be much quicker and your home much more comfortable than replacement of your windows. Research the pros and cons - go to Energystar.com to help you decide what is best for your home and your budget!