Valuation of real estate/ properties is in many countries/ cities the basis for fair taxation. The value depends on many aspects, including the physical real world aspects (geometries, material of object as build) and legal/virtual aspects (rights, restrictions, responsibilities, zoning/development plans applicable to the objects spaces). Current property valuation and taxation seems not to be significantly benefiting from digital 3D building models and/or 3D Cadastres as a result of low awareness regarding the possibilities provided by semantically rich 3D models. The current valuation practices in various countries are analyzed: Turkey, United Kingdom, USA, Germany, and the Netherlands. The (possible) role of semantically rich 3D building models and 3D cadastres in relation to valuation and taxation is explored.