Hi amigacooke --
I'm open to suggestions.
The floor:
1. Must be a PBR texture.
2. Must be a neutral colour.
The backdrop:
1. Must be "appropriate".
2. Must be a spline.
3. Preferably transparent from the outside (like the brick wall).
4. Preferably does not cast a shadow (like the brick wall).
Satisfying 3 and 4 would allow me to use it on all three sides.
Phil