Wow, we offer our clients SSO integration completely for free despite it being a bit of a fiddle sometimes, and I don't think it crossed anyone's mind to charge

Wow, we offer our clients SSO integration completely for free despite it being a bit of a fiddle sometimes, and I don't think it crossed anyone's mind to charge extra for it. Granted it's a breeze now we're using Auth0, but even before when I was wrangling an IdentityServer4 app I bashed together it wasn't that hard.