We renovate a unit of an apartment in Tokyo. The floor are is around 1,000 sqft and 6 people (2 adults and 4 kids) are going to live in this space. There are not much space especially for kids to play so we put extra floating watchtower in a room. Kids can play either in or under the watchtower. Also, two kids rooms are sitting behind TV shelf and the doors to that rooms mimic the wall so that kids can feel like they are entering secret rooms. Actually, these rooms face to corridor too, so they can migrate around the house. The interior of the house is, on the other hand, relatively chic so that the adults don't have to feel like they have no place to stay.