A residential unit is a part of (use is residential function) accommodation object (vbo) for residential purposes that, from a constructional point of view, is permanently intended for permanent occupancy by a private household, and meets all criteria applicable to dwellings. In case of missing kitchen and/or shower, a common facility within the building must be present. The relevant building has a residential function as its use and optionally one or more other use functions, and is suitable for occupancy by multiple private households.