Martin Lefkowitz. Unless you're planning on staying awhile, getting the OA in your own country is still the best option, and certainly for six months. The medical certificate as
says can be a pain, although in Australia I never had a problem getting it from my own GP (who's got 30+ years of my medical history) without any tests at all. The mandatory insurance, if you have to buy a 12-month policy, can be cancelled when you leave and you'll get a pro-rata refund.
are correct. Immigration are incredibly anal with this detail. In their minds only Thai bank accounts can be trusted, and even these need to be authenticated by the bank. Anything foreign is a fake, forgery or illegal and cannot be trusted. Remember also the transfers must be done for each calendar month. Having two in February does not make up for none in March. And not one baht below the minimum amount or it doesn't count. Although the monthly transfers is by far the best method for extending a visa, it does require careful monitoring.