ok so now that USD and AUD are at or close to parity it seems fair to comment from an oz point of view. Having lived in LOS for a year as aprt of my adventures I feel somewhat qualified to comment...i rented an appt in bkk and patts at an ave of 30k pm, now thats reasonable and in both cases the places were acceptable...my view is that if you want to have a frugal lifestyle then realistically 30k may be doable.....but i was thinking 100k in baht per mth split as follows -:
Rent - allow 25k pm on a longer term rental deal
Food and supplies - allow 5k pw or 20k pm, have 2 meals a day at home, eat out once a day.
Medical insurance - based on quotes I have checked then allow 2500 a mth.
Car - I would not have a permanent vehicle as the holding costs etc are too high. Instead I would allow say 8k pm for travel and related costs.
Contents Insurance - not 100% sure how this works exactly but assume its available at say 500 bht pm
Travel - to bkk or other parts of thailand say once a mth, allow 10k
Entertainment / Gifts etc - Allow 24k pm, very rough and will vary mth to mth.
Contingency - 10k pm
Now this is a pretty rough budget but in my view could be sustainable in bkk or patts....but if you lived in patts you would need to be disciplned about nites out and your chosen lifestyle.
In summary I feel a base of about 40k would be acceptable and only IMHO!