jonesthepost
I know exactly what you are saying and yes either 500 or 560K allowance and in fact gone up to my local Revenue office in Kanchanaburi and been asked "Do you have employment here and yes my income is less than 560K and this includes a wife's 60K personal allowance.
Yes, you do not need a Tin in that case and also told them have a pink ID card and they stated you could use it but not giving you one for the reason above and no employment.
Also asking about any new forms and they do not know and some suggesting using old forms as mentioned in other posts but may go up again but a local Thai friend whose wife knows of someone in the Revenue has stated the same and unless one sends a form just do nothing.
Yes, have also read that one has to submit a tax form but if one does not have tax to be paid one stiil has to?