also the immigration officer can be investigated and if he's caught, all of the visas he issued incorrectly are cancelled and the individuals are then leaving Thailand. I have seen several posts over the past 2 years where this has happened, so it does happen.
as James and others have stated banks give a terrible exchange rate. Go onto the Wise site ads they have a comparison tool (Wise are not always the cheapest) and compare it to how much you will get from your bank ( I am presuming your UK bank is a high street bank).
I would also get a Starling or similar bank debit card. I sometimes withdraw cash using this card and use it in Thailand as they do not charge fees and give a great exchange rate.
Am I missing something here, apologies if this is a dumb point.
The annual increase is likely to be around 2.5% a year or about £275. The flight back to the UK will likely be about 4 times that amount and then you need to live in UK for 6 months at a much higher cost of living.
I realise the amounts multiply each year, but even so, is it not worth staying in Thailand for several years before a 6 month stint in the UK?
if you don't have enough time before travelling, you can enter Thailand first, but you will probably need an agent to help you open a bank account without a long term visa. Once you have opened the account, deposit 800,000 and apply for the non o retirement visa.
Get a non o retirement visa before you travel to Thailand. Then when you arrive open a bank account and deposit 800,000 baht in it. A couple of months later you can get a 1 year extension, that can then be extended annually.
Don't buy a condo, rent instead as you might need the £50k to supplement your pension. Thailand is undoubtedly cheaper than Spain to live.
I don't know how many places you have been to, but consider other areas before you settle on Pattaya, I can recommend Hua Hin, but it depends what you are looking for. Good luck.
it means because you don't have a bank account with 800,000 in for the extensions each year you are unable to satisfy the visa requirements and have to use the agent again.
It's worse than that though, as it is illegal, so if the Immigration Officer is investigated, they will cancel ALL of the visa that were approved without the required conditions satisfied. You would then be forced to leave the country. I have seen several posts from people complaining this has happened to them over the past few years, so it does happen. My advice would be to use an agent to help open a bank account for you and then deposit your own 800,000 and do everything else yourself as it is easy. Good luck.