As a point of reference, you can get a business visa in Japan by starting a company with about $50K in capital. The idea is that the company has enough money to pay your salary for a year or so (the $50K is a minimum and depends on whether or not they think the company can look after you as an employee). I have heard that similar kinds of visas can be obtained in some SE Asian countries, so I'm guessing that Thailand will introduce something similar -- so a few tens of thousands of dollars (I'm not entirely sure what the cost of living is like there, but it's probably lower than Japan).