Indications from ATLAS and CMS of a potential new resonance at 750 GeV have seen a wide range of models put forward to explain the excess. Obtaining precise theoretical predictions for a given model can be a formidable computational challenge. On the other hand, relying on simpler analytical approximations often leads to important subtleties being neglected or missed. Here we describe extensions to the Mathematica package SARAH and
the spectrum generators FlexibleSUSY and SPheno that enable the automatic calculation of the required diphoton and digluon rates, including crucial higher order corrections, in a large class of models. We have implemented a large number of models presented in the recent literature. We explain how these may be used to rigorously test the proposed models, emphasising cases in which the use of the tools makes a significant difference to the final
results. We then formulate a new SUSY model capable of accommodating the diphoton excess with a large width, and demonstrate the utility of the set-up by studying the new model in detail without having to neglect physically important effects.