that's what Immigration suggested but UK embassy don't do them. We can only get emergency travel document😖 Your info might help someone else though so thanks
have a look at the OA on the thai embassy website. It takes a while to get your ducks in a row as you need the police check & doctors note (which was the hardest thing for us to get) Don't apply too early as the click starts ticking once it's been issued.
Look at back packer insurance we used big cat as it's extendable if you stay more than 1 year, also don't forget to get an international drivers permit before you come, it'll only be valid here for your 1st 3months but it's a start.
Good luck, you'll love it. Feel free to pm me if you have any questions & no you don't need an agent!
The longest is an OA visa applied for in the uk is valid for 1year, as it's multi entry you can leave to a neighbouring country & return before the expiry date & will be stamped in for another 12 months assuming you have insurance for the length of your stay. With this method you get very nearly 2yrs & can keep your money in the uk if you want to.
The other option is a Multi Entry Tourist Visa which is valid for 6months for a 60day stay whuch can be extended by a further 30days once in Thailand after which you would need to leave & return. This would give you upto 270 days if timed right.
It is also possible to arrive visa exempt for 30days which can be extended by another 30. Again you can leave, reenter & repeat but only officially allowed 2 per year & I'd reccomend leaving for at least a few days inbetween.
Which is best for you depends on the funds you have availble & how long you want to come for. For a permanent move I'd reccomend either an O visa or METV then set up the bank requirements & do an extension based on retirement once you're here