the thing is, I've been in a few situations where clients require an official audit. Maybe it is a bit different in Austria, where these certifications, while surely superficial in certain contexts, get you very far and in many instances serve as an entrance ticket.
If I wanna start offering this as a service, _knowing_ how to do it is not enough. As is experience in these instances. What they want, and often require, is a sheet of paper that verifies your credentials.