Contact your nearest Thai embassy .
It is a long ,difficult and expensive endeavor .
Not for the faint of heart.
Generally you make
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0 pounds a year ,by spending
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0.
How much time have you spent in Thailand and where ?
Holidaying is not remotely comparable to living and doing business.
First you need to commit to a year living in Thailand with no business .
Many do it ,many many many more try and fail .
Good luck ,it's an amazing country .
I am a bigger fan of working 6 months at home and living 6 months here