It seems like an odd question, but parts of the site and the support video state that self-hosted runners are only available to ‘Scale’ accounts. At the same time, it currently seems that Docker layer caching is still not working for ‘Free’ accounts, while the pricing page states it is.
I ask because while trying to understand the steps to set up a self-hosted runner I’m fighting with docs that could be clear and the fact that no detail is provided with any error code - so I have no real idea if the error codes are due to my configuration or just a lack of right to do something against my account.