Here’s my process.

I friend people on FL if I’ve had at least one brief conversation with them that set off no red flags.

If, on FL, they’re friends of mine, or they have 5 or more friends in common with me, they’re in. Their partner(s) too are in, provided they’re coming together.

After that, I look at their profile. Do they have pics? Are the most recent couple of pages of their activity reflective of respectful communication? Are they in with local known groups? Really what I’m looking for is: do they have something to loose if they come to my place and act like an asshat? A question mark profile with no friends? No they don’t. So they’re not invited, and I send a polite rejection instead of my address.

I occasionally get a polite message from someone before they rsvp saying they’re new, and the event I’m holding would be good for them because X. And I kinda play it by ear. Usually I invite them.

Discussion groups: So far so good. Literally hundreds if not a thousand different people have walked through my doors in the past 5 years I’ve been running discussion groups out of my home and I’ve not had an issue with property damage etc.

Parties: I did run at least a dozen parties with 50-70 people each during a time when all the local playspaces had shut down. And in those two years I lost $3-4k of stuff to theft. So I stopped. But I will say that those parties introduced a lot of people to a meaningful part of their lives and caused me to meet a lot of great friends who are still important to me and each other to this day. Would I do it again? Probably.