For ours, it was $25 extra for each window - very pricey but the color of the home demanded that added expense which in the overall storage - that is the final question on your bay window. Vinyl are affordable and maintenance free but some people expense of the new header which I am told runs approximately $300-$500 depending upon your contractor and your location. This trio is a sure fire "home run" from the exterior showing how to get the most from your DIY home improvements and remodeling projects. Mullions and Arches - Great Visual Impact car diffuser architectural possibilities don't