Something else you may want to consider mac is a yurt. http://www.yurts.com/
they are much stronger then a wall tent and take very little time to set up. Since you have a trailer already you would have the ability to move one pretty easy. Also the modern ones come with so many different options they can be insulated too you may even find you like living in one more then a house.
If you are in washington state then most of the yurt makers and very close by to you.
Neat blog, and a neat adventure!
I enjoyed your blog. Did one or both of you have sources of income that allowed you to work remotely?