[carlosrt]

The speed is what's impressive. One can build a structure in California for a similar price.

It seems people often over estimate the hard costs of construction in the first world. It's cheaper than people think.

In 2005, at the height of the building boom (labor was scarce) in Southern California, I built a 400 sq ft detached garage: Stucco, rolled composite roof, concrete slab, drywall, swiss coffee interior paint, garage door, and 30R insulation in the ceiling (well insulated).

Using all contracted labor.

Total cost: $5,500.

IOW, not much more than this 3D printed house. Building a house in 2.4 hours is the impressive part.