We bought the computer fans at a computer store. You can buy them at most any electronics or computer store.
Bill fabricated the hood. He used the same hi-lo resistor system to slow down the fans as others on the site have used. The fans are 3" 12V and do run on the battery
The floor mats are really nice. They do seem to keep the floor warmer, plus they are squishy and very comfortable to walk and stand on.
When we first camped in our trailer after purchasing it, I actually had a nightmare that I was trapped in a plastic pipe. Pretty scary. Maybe because of the smell. Who knows. Now with all the mods it feels like a warm, comfy little house (Casita). We love it.