Can I ask why would you ever want to host such a small group on your own hardware? If you think installing and configuring Discourse is difficult, who is going to be up for the 24x7 job of making sure the computer does not get hacked top to bottom? I have a background in computer security, and I can say in all honesty, I would never host my own server unless I was running something that had a guaranteed revenue of at least $1M per year.
It’s one thing to take such risks when you are implementing your personal blog. It’s quite a different level when 8K people are trusting you to protect their identities. What are you going to do when the hackers steal your user database and then start sending out phishing emails that claim to come from you? What are you going to say to the people who reuse passwords, and the stolen password works on a broker site that keeps the person’s life savings? Why take on that risk?
Properly securing a computer and watching it constantly costs hundreds of thousands of dollars per year. The people who choose to do that on their own are usually programmers and security professionals, and for them, it’s as much a hobby as it is a job. Paying Discourse $20/month and letting them watch the security logs, and do backups, and do upgrades, is cheap.
By the way, I am interested in getting a pointer to any thread you start on your FB account suspension. I run a 15K user group on FB, and they suspended my account for three weeks. During that three week period, all of my content on FB just disappeared, throwing our group into total chaos. That event alone opened my eyes that FB is a psychotic, out-of-control AI that just randomly suspends people without cause, and their backend systems for resolving such mistakes are completely dysfunctional.