Spatial planning is at the core of every economic and social development of city. Key element in the process of spatial planning is information, that is traditionally a cadastre and land book. The change in property values has been considered as the result of the planning process, but in the last decade researches have seen a huge importance of using property values data in the first step of spatial planning as additional input information. Property values data are stored and collected in the process of mass valuation. The use of these data in the process of spatial planning will enable planner to get in thouch with current state of property market in the area of interest, that will contribute to a balanced spatial development. This paper takes a new look in spatial planning process using a PSS that will be based on model as mathematical background for calculating correlation of spatial plan and property values and their mutual influence. Researched system will be connected to national LADM profile using Valuation Package and Spatial Planning Information Package extensions, which will enable international context of system.