Expect being hard to get a bankaccount straight after arriving in Thailand, even for retirement.
Banks in Thailand are like everywhere in the world, interested in having good stable customers, that have a permanent address, a steady easy traceable income, and use the account all year round.
That is why the banks are reluctant to give accounts to people on short time ( read: tourist ) visas, and who only spend part of the year in Thailand.
Don’t expect to get a residence certificat, until you have stayed at a permanent adress in at least 3 month, since that is what the residence certificat should confirm.
Furthermore the added attention on whitewashing of money, is an added burden on the banks, so reluctant depositing large amounts isn’t a guaranteed way to open an account.
The value of a resident certificat, had gone down, since Immigration Officers are giving them to people that are not on a longterm visa, or have stayed severel months at 1 adress in Thailand, so even if it is a formal requirement, the bank make up their own assesment of the stability of the want-to-be customer.
Be aware there is a error in the start of the article ( and several other copy - paste media with the same article )
A Thai Bankaccount has never been a requirement to get DTV, on the contrary it has been one of the big advantage over other visa, that you could get DTV as long as you could show 500.000 Baht equivalent in any bank anywhere in the world.
It has never been the intention that DTV visaholders should be in need of a Thai bankaccount.
Search for requirements from the specific Embassy you want to apply at, since the requirements differ quite a lot.
For DTV the 500.000+ Baht deposit can be in any bank anywhere, and you will have big difficulties with opening a Thai Bankaccount,both with and without DTV, so don’t count on that being possible.
Most Embassies recommend that you don’t apply for any visa, more than 3 months before arriving in Thailand, as can be read at the website of the Thai Embassy you will apply at.
There are also a lot of other important information on that website, you need to familiarize yourself with.