Just apply for a 90-day none O Visa, and then you can buy a one-way ticket without any issues . I just came here with a 90 day visa on my passport and now I have a one year retirement Visa. All done within one month of arriving
Your best bet is to spend your money and use a Visa service. The service I used I gave them all the proper paperwork on Tuesday by Friday I had my Visa approved and in my hand. You're wasting your time if you think you can open a bank account on your own. You will get the runaround from the Thai people.
In my opinion you should avoid none of them, they're all good they're all lots of fun just be careful. If it were me I would try to go to every single one. But I tried to do that and I almost killed myself