Well, Susan, you got a shock because Pella is one of the most expensive windows on the market. Do you want the wood interior? If so, they are more expensive than vinyl. I'm not from Chicago so I don't know which window is recommended for your area but I am in central Oklahoma which has tremendous variations in temperature and as much wind as Chicago and vinyl is recommended here. Also, I'm not replacing windows in a high-end house. If I were, I might consider the more expensive windows. But from what I've seen, the vinyl replacement windows are pretty versatile.

I would stay away from Lowe's unless you know what you are looking for. Get online and research "replacement windows" to find info on what is recommended for your area and to familiarized yourself with features such as LowE and argon gas. Be sure to get fusion welded corners for the most strength.
Stay away from Don Young Windows and Simonton.
Certanteed Windows have received good ratings from consumer groups and seems to have decent pricing. Diamond Windows are good and well priced but may not be available in your area. Modern Windows by MillCreek seem to have a pretty good reputation. I would stay away from Champion because they use high pressure sales tactics and I received a very high quote from them and their windows are certainly no better than Certanteed or Diamond.
Be sure to get multi-chambered frames for the added insullation and double pane glass is pretty standard now.

Just don't make a decision the same day as you receive your offer. Be sure to go look at some of the windows already installed -- not just in the showroom and read the warranty! Rarely does a warranty cover installation so try to find an installer who gives an installation warranty. Be sure your installer has liability insurance not just workers compensation. You are entitled to see a copy of the policy or have something in writing from the insurance company showing coverage is in effect.
There are some good web sites to tell you how to decide on windows and how to choose an installer/contractor.
Good luck.

Susan,

We shopped around for our windows and looked at several competing companies, including some of the very high-end brands including Pella. After careful consideration, we felt Feldco offered the best overall quality, appearance and value. They will come to your house and give you a free estimate and they have an incredible warranty. Once we selected Feldco, every aspect of the process went flawlessly.
After 5 years, I can share that the windows look and operate as beautifully as they did on day one. Our heating and cooling bills all went down immediately.

I highly recommend them and they have several locations in Illinois.

Hope this helps. Take care.

Here is a link that might be useful: Feldco - Illinois Window Installation

Justme

Why do you recommend staying away from Don Young and Simonton?

Why do you think Certainteed is a good brand to use?

We're also in Chicago, in a brick bungalow and need 18 windows. We thought, at first, there was NO WAY we'd go with vinyl. Our estimates have been from Pella, Andersen, Feldco, Wellington, and have one scheduled with Gilkey. Our Pella quote was almost 20K. Gorgeous windows. Andersen Renewal windows just weren't impressive for the 20K price tag. Then, enter the vinyls. Feldco which was around 11k and Wellington 12k. Both look GREAT. We were pleasantly surprised and impressed. Wellington has this unique manufactured 'wood' inside the vinyl, and the screens slide in a track (I haven't seen this on any window), which we think is a nice feature. Wellington and Feldco seemed very similar in quality and look as nice as Pella's from the outside. NBC5's "fix-it guy" highly recommends Wellington and Gilkey for vinyl. My husband thinks the Feldco's look better, they have a few hardware choices whereas Wellington only offers white, but the downside is, you cannot wash the Feldco casement windows from inside the house. So now we can't decide what is most important. Hope this helps. Since I'm here...could anyone weigh in on the washing outside vs. inside issue? Is it worth the exta $1000 or am I being pennywise?

Here is a link that might be useful: Fix it guy's window recommendations