we are flying to Thailand from France on 24th October one way with 5 big dogs to retire, we both have thai bank accounts for a year with 800,000 each and a 10 year land lease so hopefully that will be sufficient.
,I am guessing but if you can show bank statements showing a good balance you would probably be fine I am pretty sure I gave bank statements as well,my ex girlfriend worked for a large corporation and was on a good salary, just give them as much reason as possible for her to return to Thailand.
I took a Thai girlfriend to UK a few years ago it wasn't easy got rejected first attempt, she will need to have a good reason to return to Thailand also money in her bank account i think it was about 20,000 baht but can't be sure and you will need to start putting it in now our first rejection was a lump sum a few weeks before we wanted the visa ,also your best bet is to sponsor her as in pay for air fare and support her while in uk ,its certainly do able just a pain ,good luck.