I read a time ago about the myth of an expensive LibreOffice extensions and templates website. I investigated about this and had a look at the real numbers (they are public available on the wiki page: https://wiki.documentfoundation.org/TDF/Ledgers). I found some expenses only in two fiscal period: 2017 and 2018. TDF spent in 2017 6399.44 Euro and in 2018 642.60 Euro. The money was predominantly spent for content migration and an improved server environment. It included also an individual training for the TDF infrastructure team.
The most work on the website was done by volunteer work within some support from the Plone open source community. All in all TDF spent 7042.04 Euro for running the site for about seven and a half years, thus about 938.39 Euro per year. Seemed a very expensive tool in comparison to the financial and personal ressources used for running other TDF tools 😉