I still think it is better to use a visa agent the first time. Then do the renewal every year by yourself. Yes I know it will cost you a lot more than doing it yourself but no hassles. And you wouldn’t be writing in this form.
Absolutely not She would either apply for a visa from the Thai embassy in the country where she lives or apply for a retirement visa if she meets the criteria. I am assuming that is the course she wants to proceed with.
In Pattaya the bank letter is valid for 3 working days. Bangkok Bank will issue the letter for a cost of 100 THB. while you wait. You will need your bank book updated on the day you go to immigration. Plus photo copies of first page and all pages going back previous year. Sign all photocopies
The first problem is when you check in for your flight to Thailand. It is their responsibility to make sure that those passengers that do not have some form of residency status have onward travel prior to their visa allowance. If the airline allows you to board the aircraft and immigration in Thailand checks for your outbound travel. The airline can be fined and you could be sent back on the next flight