The modeling of the historical architecture can be characterized by different levels of geometric development, more or less advanced, which correspond to different values of deviation between the real object and its three-dimensional representation. The aim of the paper is a critical study of the different levels of geometry (LoG) that the architectural elements of a model can have in relation to the efforts required to achieve them and the modeling objectives. More specifically, the contribution of this study proposes—on the basis of a survey campaign of a case study conducted by drone—the evaluation of the deviation between the point cloud and HBIM models with the different levels of development in order to assess their reliability according to specific objectives, such as the documentation of the architectural asset, feasibility study, restoration project, etc.