The only other thing to be aware of is the expiry date of your passport. When I renewed my retirement extension last year I only had 6 months remaining on my passport so they could only give me a 6-month extension right up until the date of expiry of the passport. When I renewed the passport I went back when the 6 months was up and renewed for another full year.
I have previously renewed my retirement extension on the day before expiry date although it's advisable to do it earlier in case anything goes wrong like not having the right paperwork.
it may be more difficult in some cases but I don't want a Thai to steal my 1 million baht car because it's in their name. Isn't that obvious 😀 in fact they wouldn't be stealing it would they because they are the owner but I've paid for it. How many of your possessions do you have in other people's names?
it's dead easy to sell a motorbike or car as a foreigner. I've bought and sold many. I once sold a car to a second-hand dealership and had a check in my hand within 20 minutes
when you go to immigration all they are interested in is a statement showing 800k balance over the year and a letter from the bank confirming the balance. They don't want to know the source of that income. That only applies if you're using the monthly income based on pension.