question about PTSD support animals, how do people know if that would actually help or just add stress?

Honest question, what made folks here decide that getting a support animal was worth it versus just being another responsibility to manage? Because on one hand it seems like animals help some people with PTSD symptoms, but on the other hand taking care of something when you're already struggling sounds potentially overwhelming.

Sleep issues and hypervigilance make day to day functioning harder than it should be, and animals do seem to help based on posts here but it’s unclear if that's universal or just specific situations. Like is there a way to know beforehand if a support animal would genuinely help or is it just trial and error?

Also about the practical part of it, if someone's renting with pet restrictions does getting official ESA documentation actually make landlords back off or do they still find ways to make it difficult? Because adding housing stress on top of everything else doesn't sound ideal, but if the therapeutic benefit is real then maybe dealing with bureaucracy is worth it.