what type of business do you plan on starting? You set the business up first legally, which isn't too difficult using an attorney, before you apply for the type B visa extension. The problems start when you apply for your work permit tied to your business. First you must have at least bt2million in registered capital in the business, and hire at least 4 Thai employees you pay wages, and social security on. Then on a regular business setup you can only own 49% of your business. The other 51% must be owned by Thais. One of the employees must be a licensed Thai accountant. You can not do your own accounting. If your business can qualify being set-up under the BOI, board of investment, then you can own all of your business, and eliminate the need for the Thai employees, except the licensed Thai accountant, you must have that no matter what. Not every business qualifies for the BOI. It mostly applies to branch offices of your already existing business in another country, and expanding into Thailand. Then, because any business for a foreigner is set up as a corporation, you must make a legitimate profit in the business within 3
***
years, or the government dissolves the business. That is it in a nutshell. Siam-Legal.com is very good at business setups, and keeping everything legal.
if you get the DTV now any changes made in the future don't affect you for the five years your DTV is valid for. Understanding this might make your decision easier. The biggest changes coming are in relation to the soft power category as that has the most abuse, not the workation category.
in the past there were too many incidences of scamming the volunteer visa to stay here long term, and businesses charging people to volunteer. The government after awhile took a dim view to this charging tourists to volunteer.
The easiest way to transfer all the money is by SWIFT bank to bank transfer. This also gives you an FET, foreign exchange transaction receipt, that you'll need if you ever change your mind, and want to transfer the lump sum out of Thailand in the future. With Wise transfers you can not transfer the lump sum in one transfer.
Currently the Thai embassy in the Philippines is pretty straightforward, and doesn't have near the queues as the embassy in Vietnam, Laos, Cambodia, or Malaysia.