In my older age I prefer some luxuries. DJL do offer free accommodation if your taking a course, we paid £32 in Mar 2019.Well under thousand baht for a single room/cottage. NO AC/hot water required.
There are plenty of places on Koh Lanta which cost around 600B but I do expect to pay a bit more on Lipe.
I have never paid over a grand anywhere in Thailand from all my previous visit.