Having seen the info that Carol posted. I found this great site and video to watch. This is the way to build cheap homes with do it your self gear and products.
http://www.makepapercrete.com/
This really should be in the Joomla Library. I will post a copy in the researchers section.
This is the link for the video on you tube.
http://uk.youtube.com/watch?v=JoLBeV6tzJ4
Hope this will continue Carols great thread and encourage more ideas.