Some (me included) may say more trouble than it is worth if you do not have Thai relatives. You cannot own land outright in your name. You could long term lease land (10 yr, 20 yr), then you can do what you want in that time frame.
Before you sell everything, I would come to Thailand and rent for a month in several places, to see what you like.
I am not a car person at all, but I always wondered if they were made slightly different in different countries. Like radiator system, fuel additives, oil, emission standards, etc.
Go way before now! But seriously go on Tuesday (Monday is probably busy). Don't wait until the day before. If they are busy enough, they will tell you to come back the next day.
when you say "they provided the bank proof", do you mean the proof of YOUR MOM'S account with the 800,000 in it? Or they provided "proof of some sort" to immigration.
I am not a visa expert. I just know that although you can technically get unlimited visa exemptions, they will start asking questions if it looks like you are trying to live here. (ie not exploring Thailand.)
They are cracking down on that apparently. are you on a tourist visa? Or living in Thailand on tourist visas, visa runs, visa exemptions, and border bounces?