When we moved to our home we had absolutely no window coverings. And only one of our windows (the bedroom) had a screen. That screen tends to go flying out of the window when it's windy--we've had some challenges.
Our bedroom also has vaulted ceilings which are beautiful, but also included tiny square windows at the top. We were blinded for months at 7am by the sun streaming in right on our faces. And if it wasn't in our faces, it bounced from the mirror beside us into our faces. One day I couldn't take it anymore and just had to make window coverings. I used two cheap tension rods and some cheap white linen I had had for years. The entire project cost about $5 and took about an hour and a half. Here are the before and after photos: