I did it a little differently with foam core and various sizes of squares and rectangles. I'm fairly pleased with the way it turned out.
What took the longest was settling on the fabric and the arrangement. Otherwise, this is something you can do in a few hours. The cost was approximately $60 for both which includes canvases, paint, supplies, and some fabric.
I made this one first and the husband liked it so much, he said he thought the wall needed two, so I made the other one. It was hard to match the paint color which I had just blended on the spot, but it's pretty close.
Next project: big pillows for this room - stay tuned.