Generally speaking, in Thailand at an international school you could pull in about 900 USD per month.
A private school in Thailand will pay about 5-20 USD per hour and let's say you accumulate 20 hours per week @ 10 USD per hour then that works out at about 800 USD per month.
A cheap flat will cost you, say, 200 USD and living costs outside this are quite cheap.
I would say that if you are frugal and keep your living costs down to a strict minimum and if you get a job which pays reasonably well then yes, you could do it. But it won't be easy.
Of course given time you may be able to pick up some extra hours teaching here and there to relieve the burden, but that will come after time in the country.Some useful info on TEFL in Thailand