lol....I guess so....look at the guys hands under the DIY section:
Depends on what type of mount you need, or how versatile it needs to be (extension, etc). Peerless make decent mounts.
I don't think you have to worry about HDMI length unless it's super long. Just run everything through an A/V receiver.
I'm not sure what spandex is. But I think you should focus more on what the screen material does in your environment. Are you going with diffusive or retro-reflective material?
Ok well if you run everything through a receiver, then there will only be one HDMI cable going to the projector. Don't worry about the length.
The type of material the screen is made out of is almost important as the projector itself. Any type of screen you get it going to have these qualities, you need to make sure you're getting the right type for your room!
Diffusive screen material is the more common white screens. This screen material spreads the more the light evenly in all directions. They have no gain or little gain. Like 1.0 or 1.1 gain. This is best for wide viewing areas where you have complete control over ambient light, or you can make the room really dark (no windows, etc).
Retro-Reflective - this material reflects the light more directly back at the viewer or to a smaller viewing area. Gain is usually 1.5-2.0 or higher. You can have hot spots on these but they work great for rooms with ambient light or where you can't control the lighting very well. These are recommended for ceiling mounted projectors, BUT I think you have to be careful with Short Throws because they are closer to the screen they are much brighter.
I started out with a grey retro-reflective 1.5 gain screen and then switched to a white 1.1 gain diffusive screen. Both screens are great, but the white screen has a more uniform brightness in a dark room, however the image suffers with the lights on.
You need to figure this out before worrying about the frame and DIY.