There is also the other avenue of keeping 800,000 baht in a Thai bank. I plan on bringing both my Thai bank statements and my income statements when I go for the first time in November.
I did all this last year. I got my visa in the US and opened a Thai bank account after I got here. A word of advice. Make sure your bank in your home country is experienced in international bank wire transfers. My US bank, Wells Fargo, was awful and caused me big problems initially. I had to go back and change banks.