Folks, what is your strategy for replacing window? Is it cheaper to buy them at homedepot and then have carpenters yo install it OR you shop in your local window stores?

@Kate J. We buy windows from the supplier ( ABC inc) . For extra $20-30 to the price of the home depot cheapest junk window, you actually get a pretty decent one.  And we install them, ballpark in our neck of the woods - $500 per opening, labor and material. Last I heard window world was closer to $1000 per opening for lower quality product.  Good luck.

In our market the local window suppliers tend to be cheaper than the big box stores for windows. Add to that they are normally more well versed in the trade and can answer questions better. 

@Dan Bryskin does the supplier have a showroom? I wonder how to order from them?

I've replaced windows a few times in a couple of different cities.  In general, I've yet to find the best way to compare quality prior to purchasing.  Supposedly a "Fenestration" rating is a good way to do that...

Regardless, I buy the replacement from from the person or company that installs it.  So, if there is a problem, the manufacturer and installer can work it out and I only deal with the person I bought from.  In my experience, every town has one or two guys who are know for supplying and installing windows.  They tend to have the best price and delivery.  That's my strategy.

If I was in a new area where I knew no one, I'd probably pay more and get a brand name from highly rated online supplier.

@Dan Bryskin my window world windows were under $500 (9 total). I've had them a year and so far they are holding up well.

I bought windows from window world at a cost of 200 dollars a window

I buy the Series 70 Andersen American Craftsman replacement windows at Home Depot. $160 for each window (this depends on size), $10 for additional materials (foam and silicone caulk). I install myself. I could teach someone else do it and pay them $20/hr and get it done in 2 hours each.

Replacing a window is neither complicated nor difficult. There are many companies that specialize in it because it's easy money, and they market the hell out of it because it's easy money, and they use high-pressure sales and scare tactics because it's easy money.