100% you will be rejected if your unemployed. You need to be employed either with the letter from your employer or certified and signed off accounts if your self employed
London are pretty stringent on a proper letter from your employer. I certainly wouldn't get a letter to say you wont be employed whilst in Thailand. If you search the page, there are a few examples from London. Even with a big bank balance, if your unemployed, they will reject you.
If your self employed, you will 100% need certified accounts.
Thinking about going down the tax route and applying for an extension with rental income direct into a Thai bank account. Is it classed as working too? I don't know how they view rental income.
yes. I kind of had it in my mind that the OP was getting the money paid into a UK bank account when I saw he was from the UK, hence i said about the proof of income as he would of needed to deal with the UK Embassy in order to get the letter.
If I remember correctly, If you base your extension based on income in Thailand you will need to show personal corporation income Tax (PND.1) latest 3 months and personal income tax for previous year with receipt (PND.91)
You then need the supporting evidence to gain the Income letter from your Embassy.