With this contribution we aim to address some issues of increased relevance within the scope of tax law, specifically, the tax benefits for IMI and the problem of aggravated taxation directed at vacant and ruined buildings. We start by making reference to taxes, focusing on the most relevant aspects, namely, the historical background of IMI.After that, we will turn our attention to IMI tax benefits, touching on their various characteristics, and analyzing some incentives and benefits.Another point to be dealt with is related to the situations where IMI is increased for vacant and ruined buildings, which corresponds to the provisions of no. 3 of article 112 of the CIMI and no. 1 of article 112-B, also of the CIMI.Following this, and on a more practical level, we formulated a practical case illustrating a situation of aggravated taxation, and analyzed some practical situations by resorting to case law.Finally, we present some solutions that, in our opinion, seem to be the most adequate in order to try to avoid the aggravation of estate taxation.