The work is focused on the use of fuzzy numbers in the reconciliation phase of real estate appraisal. In this particular phase, could happen to observe several different values coming from cost, market and income approaches. The main issue of this work is trying to weight them through fuzzy numbers instead of normal numbers It will be shown the difference between a normal interval of value and a fuzzy triangle based on the possibility theory. It will be shown, through an application that fuzzy numbers allow us to show the complexity of real estate market in an appraisal report. After a brief introduction, the second paragraph will analyze the concept of reconciliation in real estate literature and will be offered a brief definition of possibility theory and fuzzy numbers. In the third paragraph will be shown an application. The fourth paragraph will offer some possible conclusions.