Going for #FOSS absolutely hasn't been cheaper for us than going for Msft's non-profit discount.
We value self-hosting, so we bought (refurbished) servers. We had to hire a befriended engineer to set up the platform , back-up, the provisioning, configuration management and to integrate everything with SSO + 2FA. We also have a small support contract with him because, well, imposter syndrome.
Going #FOSS hasn''t been cheap, but hopefully sharing our knowledge will make it cheaper for others.
@Gina You're not including privacy as a form of capital.
@Gina It always appear to be until you start doing it. The hidden little fees add up. But at least you have more control over your system and the warm feeling that you are running a more FOSS system.