Fourplex (click to enlarge)
Specifications: Four units, each 462 sq. ft. interior, 1 bedroom, 1 bath, Footprint: 48’x48′ plus 8′ wrap-around porches
Description: This potential investment property features numerous sustainable building features, including earthbag walls, superinsulation package, and compact and efficient design.
Fourplex (click to enlarge)
Earthbag House Plans 
Would it be possible to redesign the interior into a single unit/home consisting of 3/4 bedrooms, a large kitchen, dining room and living room? Thank you!
Yes, this has already been done. See the first plan on my Free Plans page:
http://www.naturalbuildingblog.com/house-plans/free-house-plans/
By “free” that means you can view what Structure1.com did for one of my clients. Of course, you would have to buy the plans and hire Structure1.com if you want to actually build a house.