Before moving back to my parents (I'm still studying and wanted to save some money) I lived in a dorm with shared bathroom and shower. 12 square meters. Well, living in a small flat is actually ok, especially if you are living lonely. But I'm sure, that I won't live in a small flat/home anymore, if I can afford a bigger one. It might be enough but that's it. A small home decreases quality of life too much.