A popular way to make money for retired guys in Thailand is to start a YouTube channel and talk about bar girls. Those channels do well cause old overweight men with blue balls enjoy watching that stuff
If you do land border runs with a visa run company or drive yourself to the borders they use and pay the border fee then you can live in Thailand non stop. You will have no issues. But if you fly in and out there is a high chance of having troubles.
I lived in Thailand for the past 3 years by doing land border runs and never had any troubles
The QR code is just a short cut link to their bank account. You can just ask for the account number and then transfer using wise or one of those companies with your home country account
I don't know any agencies but if you want to do it yourself and save a lot of money it's not hard to do. I paid for a 6 month training package with Phuket King for 15,000 baht and then applied. They have all the correct documents.
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