@Lloyd *******
as somebody put it well on here the other month, here is the full potential with your six-month METV:
* Enter first time for 60 days = 2 months
* Extend at immigration (1900 baht) for 30 days = 1 month
Leave Thailand and re-enter
* New 60-day stamp on re-entering = 2 months
* Extend at immigration (1900 baht) for 30 days = 1 month
* Leave and re-enter Thailand just before your whole six-month visa expires
* A new 60-day stamp on re-entering = 2 months
* Extend at immigration a final time (1900 baht) for another 30 days = 1 month.
Add these up and you have a possible 9 months.