Dallisgrass. MSMA for existing weeds and prodiamine to prevent new seeds from sprouting. Keep lawn short to prevent seed heads from forming. Spreads quickly if left unchecked.

Best to take the shade with you when shopping, then you will know exactly the size. Otherwise, measure all the points.

" I believe cedar shingles only come in one color and that is how they look when they age. " False. Cedar shingles come in several different species of cedar, cuts and various "factory" finishes or could be finished with almost anything in the field. Most likely it is a Cedar Shingle siding and roof and the vertical a T&G, possible center matched as opposed to a vee-joint. Look at 18" Western Red Cedar Perfections. The roof looks natural to me but the siding definitely has had some sort of finish/stain applied to it.

Andersen Window. You can get those from an Andersen Dealer or from Blaine Window Hardware.