I've watched a lot of shipping container home builds on Youtube (everyone ranging from amateurs, to professional housing contractors doing their first shipping container builds). The people who spend a lot of money seem to be the ones who want to make a shipping container feel like a traditional house. The people who build them affordably respect that they're living in a shipping container, and integrate the container aesthetic in to their home.
I'm wondering where the building regulations are so relaxed that a shipping container can legally be converted to an apartment. Definitely not in the parts of Europe I'm familiar with, but then again the weather conditions in most of Europe probably wouldn't allow for it anyway.
At least in the U.S. when dealing with building inspectors you describe your house as a "prefab steel-frame building." I've seen container houses in the E.U. also, so certaintly they have some kind of regulatory framework for dealing with these too.
From what I can tell these things can pass building codes if constructed correctly, and also when communicating with the government clearly. The bigger problem is them passing zoning / architectural review that many local governments requires to keep a certain aesthetic in the neighborhood.
