Below is a list of cult markers I posted here the last time this came up. It recaps some of the bullet points above.

1. Apocalyptic world view.

2. Charismatic and/or exploitative leader.

3. Insularity.

4. Esoteric jargon.

5. Lack of transparency or accountability (often about finances or governance).

6. Communal living arrangements.

7. Sexual mores outside social norms, especially around the leader.

8. Schismatic offshoots.

9. Outsized appeal and/or outreach to the socially vulnerable.