There is no German embassy or consul in Germany. If you apply in Pattaya, you'll find a consul named Hofer, who is equally responsible for Germans and Austrians.
Non O Retirement Visa for you if older than 50 years: You don't need a bank account or 800,000 THB in a Thai account. If you earn more than 65,000 Thai Baht per month in Germany, you can have this certified by your embassy or a German consul in Thailand. If you apply for a Non O Retirement in Thailand you need about 90 days. If you are successful, you can apply every year for a 360 days extension of stay. Once done and without breaking rules you don't need to apply for a visa anymore, only for the yearly extension of stay.
I don't know where you live, but even with a Thai driving license, you can't drive to your wife more often if you don't have the appropriate immigration visa.
Do the same what you did in Bangkok before. 1. Ask your hotel for a TM30, fill out Form TM7, make the copies of your passport = 1900 Baht. 2. If you need help, take the service of the "yellow Shirts" beside the Immigration for 200 Baht or 3. take the help an agency for 4000 Baht. There are the 3 options, but you need the TM30 of your hotel. Good Luck. Don't worry too much. It's easy. 😊
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