The build quality is frequently quite poor. So wonders would pretty much need to happen for you to be able to use the property for your stated 30 years
Because of the huge inflow of Russians it is now - apparently since about a months or so ago - very difficult (and much more difficult than before so all the comments that somebody did it a year ago are not really very relevant unfortunately)
There are, but you can also get a bona fide international driving licence from your home country which then is valid together with your foreign driving licence at least a certain amount of time after entering Thailand (which somebody on a tourist visa presumably does regularly)