The aim of this contribution is to determine the change in value of an older sample building assessed in the included case study as a result of its reconstruction. Valuation methods are applied, which, as it turns out, reveal the inaccuracy of the subjective view of the person who reconstructed the building. The resulting change in the value of the sample building is discussed from the point of view of the applied valuation methods and other value-creating aspects (subjective view of the owner on the value of the building, historical value of the building, etc.). The contribution concludes with recommendations for maximizing the increase in value of a property through its reconstruction so as to eliminate the risk of a decrease in its value.