The main problem will be opening a bank acct for both of you...agents can do a full package bank acct+90days+1yr if you decide to use one......if not you need to leave and apply for a 90days nonO retirement outside of thailand (with overseas funds) and once approved come back into thailand and open thai bank acct bamkin 800k and apply for 1yr extension
My experience is i have renewed my passport and collected at Singapore embassy in bkk they will issue a letter verifying the change....bring both passports and the letter to get your stamp transfer to the new passport and if u do have a multiple re entry permit they will transfer that too
They will issue u the extension up to the validity of your passport and not bringing forward the extra months.....best is apply for a new passport before doing extension
create a new Gmail and register another Google acct with the phone number that is not registered on the Google playstore...lets say your current Google account is registered with UK u create another one using the thai number
It doesnt really matter as long as it's registered under your name....you can change it to a post paid or hop onto other telco using the same number ....I've been using the same tourist prepaid since 2018 until now never have any problems