Please help...quote seems very high

I recently received a quote from a company for triple pane windows using Compozit frames for 8 windows and a slider in my one story ranch. They are replacing horrible old aluminum windows. The quote he gave me was $17,800 and that includes labor and materials. I have been doing a lot of research since he left and based on some of the information I have seen, that cost seems pretty inflated. This is a smaller company and one of his sales pitches was that their prices were more competitive because they had less overhead than the larger companies.
I live in Western Oregon, so we do not see a lot of extremes in weather, but I do want to make sure that I choose a good window.
Thanks for any advice!!!

While I am not familiar with the particular window, the price does seem extremely high. I'd recommend getting at least two more estimates.

$2,000+ a window is outlandish regardless of what the install or product is.

You need to keep shopping.

Keep looking Katherine. Let us know how you make out with your window shopping.

Thank you so much for the responses. I felt in my gut that I was being taken for a ride, but I know nothing about window costs and his sales pitch was so aggressive that before I knew it I was signing an agreement. At least I am within the 3 day period that allows me to change my mind before they get my money.