I was really considering going to Cambodia and working with an NGO, 2k in Cambodia buys you a bar on the beach (four sticks, a fridge, and a roof) sell 8 beers a day and you cover your living expenses, house on a white sand beach with two servants is 700.00 a month. but Cambodia is terrible with crime and corruption and beggars, and diseases and bugs, but still thinking about it for after my loop of the U.S. They have the fastest rising GNP and just discovered big oil reserves off the coast, Exxon will be bringing workers an infrastructure. Anyone interested should check out the website Khmer440.com
Thailand has great hospitals, but there are 1000 other serious problems there I could go into them all (least of all being terrible water and pollution) but you'd be better off reading up on expat blogs. I remember there was one mountain town where most of the expats lived, has fresh water, didn't have the wild sex clubs and was high enough to avoid most of the insect problems. They had an expat center there that was like a senior center for expats from around the world. If I don't go to Cambodia or Mexico I'll likely go there.
Oh and bob most of the expats I read about in Thailand were going to Cambodia for their visas because it's like 170 bucks and lasts for years, I don't remember all the details or why it was valid in Thailand but yeah there are lots of blogs from Thailand expats going over the terrible bus rides to Cambodia.