Depends on the install type, window size, options, and requirements.

What kind of deck door?

Just a quick assessment, it does not look like that pricing is out of range with what we see.

You are referring to the Okna 500 series also kmown as " Insul- Tec".
I agree, the price is within range for replacement.
Is this a replacement application or full tear out with all new teim and moulding?
Where are you located?
When you say deck door, i am assuming you mean a sliding patio door?

Thank you so much. They'll be removing the interior jamb and the moulding and replacing if necessary; they will not be removing any of the siding on the exterior. Sizes for most of the double hungs are in the 32x62 range (based on my quick measure of the interior opening). Yep, the deck door is a sliding patio door. I'm in New England.

Sounds like a good price for a very solid window. Good luck .

Sounds good to me. Great window.