Most important for old people good medical facilities and close enough to call police if you have problems city living or country living both have good and bad points
its got an artificial beach and one in nongkhai. The good thing about Udonthani is the low cost living and 4 good hospitals 4 big supermarkets. And nice friendly people.
baht per month? Rent a small farm and go solar and grow lots of fruit and veg. Chicken's and ducks and so on and you can have a lovely life for small money