I recommend you don’t come. Thai immigration laws have become stricter, penalizing those of us who abide by the rules, all thanks to individuals who habitually overstay their visas. It's disgraceful.
Don’t buy into that. There’s always a “crackdown” on foreigners in one way or another. Thailand does everything pretty much by the book, except when it doesn’t, which is often. Volume is key. Ask 10 random Thai immigration officers about some intricate detail regarding visas and you’ll get 10 different answers.
All you need to do is visit more branches until you get approval. Insisting on speaking to a manager and arguing your case does actually make a difference. I got rejected by around 5 banks before finally getting approved, and all this was on a 30-day tourist visa. Do not accept "no" for an answer. Keep pushing, and you will eventually get approved. They might tell you a work permit is necessary, but it's complete nonsense, as they frequently approve tourists without work permits.