I'm building and am interested in having a nice, small
decorative clear beveled glass in the staircase landing window area. I've read it's
much better/energy efficient to hang this separately as a window
"covering" against a regular double pane window. My staircase window on the plans shows a double hung window (though I can change this), and I have 1 week to decide (windows for the
house will be ordered in one week).

My questions are:

Does the type of window matter? i.e. is it easier/cheaper/better to have a picture window instead of double hung?

Is there an "ideal size" of the regular window (increasing the chance of finding something already made instead of custom making?)

Can this process be done with a double hung window? Should it cover top/bottom or only one of the two
panes, and if so, which one?

Does it matter/is it better
if the working window is operable vs non-operable?

It sounds it's best to try and find a local stained glass window company, is that correct?

I was thinking of a pattern similar to...