Inexpensive Countries for Budget Travelers

Elite Daily came out with a list of inexpensive nations for travel.  On the list:  Bolivia, Thailand, Greece, Spain, Costa Rica, Vietnam, Romania, Sri Lanka, Nepal, and Argentina.

I have heard this regarding Thailand, Bolivia and Vietnam.  I can't speak for them as I haven't been there...yet.

I lived and worked in Costa Rica and can tell you that most people might agree that it's fairly inexpensive to fly to (from the US, at least) but I think we'd argue the cost of an actual vacation there.  In fact, I often hear complaints about how expensive Costa Rica is compared to how inexpensive it's perceived to be.

I would add Peru to this list.  I found it to be a country that was much less expensive than Costa Rica with a great deal of options for travelers within the country.  I got a killer airfare mistake out of AeroMexico, so I'm sure the airfare would contribute to its being more expensive to visit, but two of us spent very little considering our 10 day trip and travel between multiple cities.

Any thoughts on the countries on the list or others you would add?