If you’re in a private Facebook group you’re in a membership site. That’s a great free way to get started.
Another way to think about it is an email list. The OAAF list is a set of ‘members’ who receive information and exclusive offers from the OAAF.
Aweber and GetResponse are a couple of email marketing providers. They used to offer free trials.
You own an asset when you have a list of members (Facebook group, email list, etc.). You can share private invitations, ideas, and opportunities with anyone in the group while excluding everyone else. You can also segment the group to certain people such as officers/admins, people who live in a certain location, people under a certain age, etc.
I hope this helps.