Abstract. The present thesis makes an effort to embed geographic metadata in operational functions of online Real Estate GIS applications. Part of the current work was the development of a functional application proving the viability of such an approach. The whole effort was more or less as a proof-of-concept approach rather than a full commercial effort. Basic motive for the particular idea-application was the personal discomfort during the phase of real estate search for renting/sale. Due to the fact that, similar solutions have been developed worldwide, the idea does not compete so much for her originality as for promoting best practises in the Greek market. The idea of using such an online service for free or for a very small fee without extra charges based on the price of the real estate, is an action extremely "democratic" because the information becomes available to the masses. Since Dwelling Construction constitutes the basic pylon of growth for the greek economy, the availability and diffusion of information will accelerate the growth, decreasing the purchase cost of residence (no need for RE agents) at least for the smaller estates. Individuals will select the estate that will really satisfy their needs in the best possible price. Moreover, the sector of RE will mature through the specialisation of brokers / RE agents, in areas like RE leasing and Investment assessment.