This is two 40′ insulated containers placed 8′ apart with a roof built over the entire footprint. Alternately, a 40′ half-height container could be placed over the space between the two containers and an uninsulated roof could be applied to the top. Half height containers are used for shipping really heavy stuff and are available for purchase used. The nice thing about this layout is the amount of space for mechanicals and storage in the half-height overhead container. If extra tall containers are used for the two base containers there would be ~9′ of interior headroom, which would make the relatively small space seem roomier. I don’t see an advantage here in cost. For the amount it would cost to purchase, haul to the site, lift into place and altered to make the containers livable, you would be very close to the price you could stick build a house of the same square footage.