Have you met Mr Gaines-Cooper? You soon will. And not for the financial smarts that earned him a fortune in the Seychelles…

In a landmark legal decision now curdling the cocktails at a thousand expat watering holes in Thailand and around the globe, Mr Gaines-Cooper has bought lasting fame at a price of about £20 million.

Robert Gaines-Cooper had told the taxman to leave his fortune alone, claiming non-resident status. But Her Majesty’s Revenue and Customs successfully grabbed a slice on grounds that could cause many expats to shudder.

To be a non-resident of the UK it is no longer enough not to live there. Now, you must also be sure not to regularly visit – or to have property, a phone number, a sports club membership, commercial interests or a bank account.

Paul Gambles of MBMG International advises British expats in Thailand to swiftly overhaul their affairs to avoid being liable for tax on worldwide – rather than just UK – assets and income.

‘If you are not prepared to change your life, then the thing you might need to change is your entire tax planning,’ he told the Bangkok Post.

In the short term, the Gaines-Cooper ruling could take the shine of overseas living. That said, as Western governments scrabble to refill their empty coffers, Thailand’s wonderfully low cost of living looks more appealing than ever.

Taxes are on an alarming trend for citizens of bankrupt Western nations. If, as Paul Gambles told the Bangkok Post, Europeans may soon have no shelter from their destitute exchequers, they may as well live somewhere cheap.

‘The big concern is that the next step by the UK and all the other indebted Western governments will be to move to an American-style tax basis – where all citizens are liable to tax on worldwide gains and income, irrespective of their residency status,’ he said.