You need 4 thai staffs on payroll, contributing social security. Your girlfriend will probably be the 51% (juristic person) for the company. Lots hurdles for you to apply Non-B and work permit for the start up.
I got pulled few days back at swampy for reason of long stay. Questioned about my Thai child and why didn't I get a visa... told me to get a visa or next trip will be a no entry.
As of now, nothing from Singapore side. The carrier had confirmed that it will be enforced tomorrow 21st 2359hrs. I got my boarding pass and waiting at air side now
You can apply via the thai embassy https://visaonline.thaiembassy.sg/index.php and submit your documents. Drop them an email:
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and submit your documents. Drop them an email: consular@thaiembassy.sg if you wanna use your ROM certificate. They probably issue you a 3 months visa. They are quite helpful and responsive.