We do windows - Pella to be exact.

After getting bids from several different suppliers, we're putting Pella Impervia windows in the cabin.

Now, I know what you're thinking: (Pella!? This guy can't be on much of a budget. Those are expensive!)  Well, they are more expensive than the typical baseline windows, but not that much more.

I got a tip from a friend to try Lowes.  Lowes carries Pella and you can custom order sizes, finishes, etc.  And they are MUCH less expensive than ordering direct from Pella. AND Lowes is having a 15% off sale until July 18th.

A few changes to the original design after working through everything.

• The Pella Impervia have fiberglass frames, and we added foam insulation (to reduce cold transfer) and added the high-altitude modifcations because we're above 3600 ft.
• I reduced the sizes to 3'x6' casement windows from 4'x8'. It's REALLY hard to find 4x8 windows that aren't custom and/or unreasonably priced.  And a 6' tall window allows us to install them 2 feet above floor grade, eliminating the extra charge for tempering the glass that would otherwise be required if they're installed closer than 24" to the ground. (The are additional requirements in the International Residential Code-the IRC-that require opening restrictors on windows on upper levels.)
• 3x6 also allows us to add another window across in the bed and bunk rooms and the family room), thereby maintaining overall glazing area (and the views!)
• In each bedroom, we have one casement window to comply with egress requirements.  The other windows are stationary, picture windows.
• In the family room, we're stacking 3x6 picture windows with 3x1.5 awning windows to allow for venting.  We'll better fill the vertical wall space with glazing to take advantage of the views. 
• In the basement and the powder room, we're putting 3x3 casement windows.
• The frames are black both inside and outside. We think these will go best with the rough sawn wood we expect to put on North and South facing walls on the interior; and with the corrugated sheet metal and charcoal colored hardipanel on teh outside. 
• To the fiberglass frames, we added the foam-filled option -- very energy efficient and durable. I thought about wood on the inside. Although it's beautiful, it's just too expensive and would require ongoing maintenance. 

I want to build this cabin just once, and to build it *right*. I also don't want to spend every waking moment on maintenance. The fiberglass frames should have a long life with no maintenance.  I've learned over the years that it's cheaper to buy the right thing once, than to buy the wrong thing first and then the right thing afterward.