PreFab Kits - the metro Cabin

The Metro Cabin is a kit that can be put together in 3 Days by 2 people. It uses high quality materials and is guaranteed for 25 years with a limited warranty. At 16' deep x 20' wide it has generous room. It has an expansive, airy feel due to the ceiling height which is 9'-9" in the front. This system is constructed of treated timber perimeter wood beams, engineered joists, and 3/4" wood sub-flooring. The walls are stud-built with wood siding on the exterior. The cabin is trimmed in durable, high-grade spruce wood throughout. The curving galvanized steel beams support the 2" x 6" tongue-and-groove pine roof deck.


Prices start around 32000 and then the options kick in, a kitchen, a bathroom, etc.
They have worked with Ikea to create some interior options which I am sure you could do as well.
They use the instant heat water system which might not be good for a solar rig.
You will have to build the deck your self which would expand the living space of the cabin greatly.
There is also a need to find a way to insulate, heat, cool the structure as well. I do not see any of these in a snow setting. 

The company also offers the metro shed as a temporary office. 
I am sure a few of these could be tied together to create a more livable space for a family.