We have recently published our whitepaper on the TCO of Modern BI implementations. The study was in three parts.
First we created a BI TCO model. We call this the BI Value√ TCO framework.
Then we interviewed seven large corporate users that used Tableau, assorted legacy BI solutions, and several other modern BI tools. We used this data to populate the framework and set assumptions.
Then we applied the framework to compare the TCO of market leaders Microsoft Power BI and Tableau.
The paper is available here: https://www.tableau.com/resource/total-cost-ownership
Of course, the IIIE is available to consult with BI buyers to assess both their readiness and cost of implementation.