What are the best methods for finding long-term accommodations in Thailand, and are there good groups for this?

Renthhub.th is very helpful, found my apartment during 3 hours only in Bangkok

Have a thai friend and walk into desired condo buildings at desired location and ask Juristic office what’s available.

If using facebook groups, have a thai friend help you look on the thai language ones, and let your friend do the talking.

Or look at websites like propertyhub, ddproperty etc,

To find best deals, walk-in with Thai friend helping is likely best.

Its a freakin jungle, same properties gets listed at different prices multiple times on same sites and groups lol.

Search: condo and city you're in, and you'll find dozens of groups.

Market place on FB has many options ,just set the location on it and any filters and your options will appear 🙏🏽

Many, you'll have to search city by city on FB