Re: DIY screen
Paint on drywall with a black border can make a great screen with the correct paint formula and a VERY flat drywall.
Other options are plastic laminates and painted masonite hung for a screen. I thought about that but I couldn't find a piece large enough at a good price that would work for me. Parkland Plastics sells a product product designed to cover the wall in a bathroom but works great as a screen. The last time I looked it was about $60 plus shipping.
I went with the tried and true cloth material route. I made a frame from poplar, cut with a power miter saw, held together with L brackets. The border is made from door casing with decorative squares in each corner That is held together with 1/8" strips of masonite. I built the frame and checked it for square at each step. Then hung it on the wall as a test. I attached the material (Hancock Fabrics blackout cloth) using a power stapler making sure that the cloth was wrinkle free. I centered the border on screen and tacked it with a few brad nails. I did this in case I wanted to remove the border and test different paint formulas on the screen. If I didn't like the paint, I was out a few hours and $10 worth of cloth.
Here's a pic of the screen frame during the test hang. That's my ugly mug in the pic.

Screen completed.

If you look at the screen in the top corner of this pic, you can see the decorative corner.

Paint formulas can vary from a simple gray to more complex ones. I just read about one using a brilliant white mixed with an aluminum paint. The aluminum give it a gray look but will actually reflect light better than regular cloth.
-Robert