What do you call this type of house?
They're called mobile homes because they are manufactured in one place and then moved to where they are needed, rather than being built on the site where they are needed. Very often they are never moved again, but they can usually be moved if necessary.
It doesn't look at all like a cargo container to me, but perhaps that is a matter of opinion.
The photo depicts what is commonly known in the U.S. as a trailer home, mobile home, or simply a trailer, situated in a mobile home community or trailer park. A friend's wife, whose father manufactured them, preferred the terms modular home or prefab home, but these are not in common use outside the industry; the industry association's name is the Manufactured Housing Institute.
These should also be distinguished from motor homes, which are self-propelled, and which may be known as recreational vehicles (RVs) or caravans in different parts of the world.
Despite the terminology, modern mobile homes tend to be fixed permanently to a location; they are mobile in that they are prefabricated and then towed to their place of installation. Mobile home is a somewhat more neutral term than trailer or trailer home as the latter is associated with poverty and negative stereotypes of the rural poor, i.e. the trailer trash.