The answer is not the length of the video! So how long does it take to set up and teardown a virtual reality setup in a small room? Add in a mixed-reality setup and you have a few complicated components like a green screen. Basically, you need to set up
1. The headset
2. The cords
3. The green screen
4. A webcam
5. Move furniture
I've added in my weird hanging VR bungee system because I consider it an essential part of my personal room setup. Obviously, most people will skip that component. But they shouldn't. Everyone should have a Virtual reality bungee suit of their own.