You should definitely go there and look at it if your are at all considering it. If you can't contact the builders directly and find out what other projects they have been involved in (other Earthships they may have helped on), and why this one ran out of cash, and what the state of their Unearth Enterprises ltd is presently... I don't know. Full plans should come with the building/property... No? The building inspector will eat you alive without the name of the structural engineer who the guy mentions in the video. You need that engineer to put his stamp on the build. Period. I wouldn't go forward without that.
Def not Bermed on all three and lacking winter slanted front... Still trying to find out if it's south facing.