Asking for Price Breakdown

When getting an estimate is it fair to ask the installer for a price breakdown, so that you may see window cost and installation cost separately?

i dont know of any company that breaks prices down that way, particularly the one's that install the better quality brands. each company has various overhead costs and so forth.
asking them for a breakdown is like asking how much profit they are making..some companies may view that question as kind of inapproriate .
keep in mind, many of the better quality brands are sold and installed by select dealers and they have to price window with install only.
installs can vary a great deal per window for a basic replacement.. of course a " jack of all trades" handyman that knows nothing about a proper install is going to be the cheapest but that is just not a smart cost effective move.

You can ask anything that you'd like, however it may not make for a fair comparison. Most dealers sell their windows "installed", and figure out their profit margin based on that. If they break it down, one dealer could make his profit on the window sale and sell the installation near cost, while another dealer could be vice versa. Many dealers don't even add markup to each separately, but only to the final installed price... Ultimately, in comparing company A, B, and C, you want to make sure that the products and installs are comparable, and then look at the final price, regardless of product vs installation, extra fees, discounts, etc.

We break out the "labor" costs as a result of the 2009 Energy Tax Credit, but that was largely based on the IRS requiring about a 20% labor cost vs. qualifying material costs.

The 20% is in no way an accurate reflection of our cost of labor or doing business so don't put too much faith in those numbers you might get.

You also need to compare the final prices and what you are getting for each as compared to trying to dissect it too much.