[type] This field is a repeating element for each type of room selected in the RoomType field. For every RoomType there are two possible implementations. For a flat implementation (RETS 1.x only), each RoomType used is expected to appear as the "[type]" in the related rooms field name. i.e. RoomKitchenAreaSource.
A relational implementation of rooms must omit the type from the field name and use RoomType to create a vertical representation of the various rooms. i.e. RoomAreaSource.