I had to do this in December 2021 as I had veen stranded in a remote area of S.Philippines for 668 days due to covid. Once you have got your stamps transfered to your new passport do this:
When your visa is close to expiry date leave Thailand and come backafter it has expired. You are now starting from scratch.
Enter on tourist visa or visa exempt.Register TM30 where you live
Go to Changwattana immigration and apply for 90 extension.
When you have 30 days left or more on the 90 days go to same place and apply for Non O retirement.
Show the money in the bank. Make sure you take your bankbook and deposit 100bhat that day to show it is up to date and provide 3 months statements (go to bank the day before and request printed signed copies of last 3 months accounts and a letter from bank stating this is accurate).
Take proof of where you live (rental agreement or book) and a hand drawn map of the area you live. Pay the money and if all goes well you will be stamped for 1 year then just repeat every year....so simple
p.s. get photocopies of every page of bankbook/passport/bank statements. Don't get colour copies, mine were refused once as the Immigration Officer said they were "Mi swy" 😆.
Once you have your stamp go and apply for your re-entry.
It is a question of risk v's reward!! She could contest but the financial and emotional costs would be extreme. Is the estate worth that much stress and uncertainty. As you say there is already a will. Is there a relationship with the grown children that could possibly kead to an amicable settlement? If not I would seriously consider if it is worth it.
A good solicitor will give you good advice a bad one will lead you astray.
A Thai female friend of mine recently became widowed to a US citizen. They had 1 child together who was in full time education here in Thailand. He was ex US Military and had a small company pension. I do not believe there was any will. I wrote to the pension company with copies if birth, marriage and death certificates and they paid out what was due to the daughter (not mother), daughter had dual nationality.
The military pension had to be dealt with in Manila, Philippines (US SE Asia office for all things related to death of US Citizen). The process, for a Thai lady who has good verbal english but not written, was a nightmare!!! Too much legal jargon and form filling. I made some phone calls on her behalf and they said they would call her with someine who spoke Thai, they never did!!! After some time she gave up. She would have received around $200 per month!!!!
My landlord downloaded the section 38 app and created an account (takes 5 minutes) then they gave me the username and password. I downloaded the app and book myself in everytime now.
It is not a question of having the funds..... It is the fact that the requirements listed on the back of the form say nothing of providing bank statement nor does it on any gov. website or agency website.
If it is a requirement it should be advertised clearly so that individuals can come prepared to the immigration office.
Some people travel long distances to get to their local immigration.