Quick post to write up how I built a retractable green screen mount on my wall for not much money.
I bought a mounting bracket from Amazon that was intended for paper photograph backrounds like this. I didn't want paper, I wanted muslin for it's superior light disbursement and durability. I already had a 9' by 15' muslin green screen backdrop similar to this one.
When the mounting bracket arrived, it said to use a metal rod with a 2" (two inch) inner diameter. I didn't want to use anything that heavy, so I went to Lowes and found PVC pipe with 2" inner diameter and bought a 10 foot section.
Then I measured the target wall and found it was 11.5 feet wide, perfect for my install. I did the math to center the mount on the wall, accounting for the several inches of the pole-mount that stick out from each side.
Then to secure the backdrop to the PVC tubing, I reinforced the backdrop with Gorilla tape every 12 inches. Duct tape or any other strong tape would work fine. I drilled a hole through the reinforced backdrop and inserted a wood screw and washer to keep the backdrop secured to the PVC pipe.
The whole thing took about an hour, mostly because it was awkward working with such a wide format project. I called my kids in randomly to help when I needed an extra set of hands.
It was really inexpensive, and I can add two more backdrops in the future if the need arises. Far better than the $1500+ solutions I found at photography stores, and much less intrusive than the nasty stands that take up too much floor space.