The redevelopment of the former Philadelphia Navy Yard is an excellent opportunity to study the reduction of the energy footprint of a campus of existing buildings through retrofits. A variety of companies and other organizations provide software, tools, or services for performing energy audits and making decisions about energy conservation measures to implement. However, these methodologies have limited validation and benchmarking. Currently, there is no standardized procedure for either data gathering or data analysis. Data on Building 101 at the former Philadelphia Navy Yard was gathered by three separate companies. The data was used by four companies to make energy saving retrofit recommendations. The audits varied widely in the values of the data gathered and did not even agree on basic information such as building square footage or condition of the windows. In addition, the auditors reached vastly different conclusions about the type of retrofits possible in the building and the potential energy savings of those retrofits. Some of this discrepancy may be due to the use of different and proprietary analysis platforms between the auditors in addition to built-in predispositions to favor certain retrofits due to familiarity or other subjective factors. Improved standards for data collection and definitions of terms used are needed. Greater transparency in modeling or assumptions and listing of the ECMs considered and rejected would aid the energy auditor in the decision making process and in providing better insights to building owners. These lessons learnt are being incorporated in the DeepRetro tool, an advanced retrofit tool and methodology being developed and demonstrated at the Philadelphia Energy Hub.