This House Can Be 3D-Printed for $4,000

I think this is fascinating, not just because of their focus on the developing world, but because I would gladly put one or two or three of these in my backyard.

Let's assume that $4k is just production cost and that finishes are another $6k (because we're fancy). That means I could put 2 of these in my backyard, adding 1400 square feet for $20k? Deal!