Should One Move to Nicaragua, Costa Rica or ... ?
I regularly get asked some version of this question. I already wrote a book on one piece of the long answer. This post is intended to try to point those who are just looking in the right direction. The answer is not monolithic: the right place depends on who you are and what you want. My answers primarily address those who are living in the U.S. Adjust the answers depending on your living situation.
My own path initially lead me to Costa Rica and then, after consideration of other places in Costa Rica and Panama, to northern Nicaragua. That was right for me but it will not necessarily be right for you. My focus here however, will be looking at Costa Rica, Nicaragua and Panama as the three primary considerations.
One big question is how do you feel about living in the U.S.? If your answer is along the lines of "I'm OK with it in general but I want a better climate and/or a lower cost of living", Costa Rica is worth considering. If, on the other hand, you are looking for serious change and feel prepared for it, Nicaragua is probably a better choice. Panama is a bit harder to explain because it offers some distinct options with much less of a meet in the middle option.
For some it may be a good final destination. For others, it may be a stepping stone. That is, it will offer enough familiar to keep you happy but have some serious advantages over where you came from. I will be the first to admit that I moved to Costa Rica without much evaluation of alternatives just because it was an easy move. While I didn't know it at the time, it was to just be a stepping stone. I am not sure I needed that stepping stone but it clearly did make my move to Nicaragua two years later a lot easier.
If your interest is either urban living or living within a short distance of urban areas, Costa Rica is a plus over Nicaragua or Panama unless you happen to like seriously hot weather. San Jose, the capital; Alajuela, the second largest city and where the main international airport is located and a lot of smaller urban areas are all located in what is called the Central Valley. It is a valley but at an elevation where the weather is warm year round but not killer hot like it is nearer to sea level in the tropics.
You will also find an array of shopping malls, freeways, nice hospitals, supermarkets and so forth. Tossed in with these familiar things are people who, for the most part, think of themselves as white and think that Costa Rica needs to strive to be like the U.S.. The good news is that this doesn't mean big military spending or the lack of free health care. It seems to mean more TVs, more cars, more malls and, in general, more personal excesses.
You get a relatively conservative government that is a lot more in your face than in many other countries but with some pluses for the consumer such as a non-profit (government run) insurance system, electricity utility and telecommunications utility. In addition, wherever you live, you are only a few hours from a decent beach.
Outside the central valley, you get away from a lot of the let's be like the U.S. attitude but most areas tend to be lower in altitude and, thus, fairly hot. That works for your beach trips but most people would rather live in an area with a more moderate climate.
If Costa Rica is want to be like the U.S., Nicaragua is more like the Wild West. Managua, the capital, is at a fairly low altitude so it is hot there. Unlike Costa Rica, most of the population does not live in Managua. There are a lot of people there and also in other lowland cities but, for the most part, cities are either near the water or at higher altitudes. Even Leon, the hottest of the big cities, is only about 30 minutes from Pacific beaches.
If you are looking for nice weather, you are more likely to end up in the northern parts of Nicaragua. Estelí and Matagalpa are the two biggest cities but there are many others that offer fairly decent weather. The big difference is that while these cities are fairly large, they are much more like the Wild West than any city you will encounter in Costa Rica. While electricity, water, sewage and telecommunications services exist in all the cities, you will find minimal levels of police, firemen and such. Along with that you find minimal requirements for building permits and inspections, or any other government control.
You will find government schools, health clinics and hospitals scattered throughout the country. All of these services are free but you can upgrade to private institutions if you wish. This minimal government service but freedom to do what you want sounds like the ultimate Republican dream. I am actually not sure it isn't.
While the government here gets assigned a lot of labels (from crooked to Communist), it isn't clear how much that matters. That is, the government offers some minimalist services and continues to do things such as build roads for the common good but, not that much else. And, in return, having that kind of government is not expensive. Thus, more of why it is like the Wild West.
This freedom may seem scary if Nicaragua is your first foreign destination. That is, you may be looking for more guidance than what you will find here. On the other hand, if you are creative and don't want someone looking over your shoulder, Nicaragua is a nice place.
Let me say that I know a lot less about Panama than Costa Rica or Nicaragua. The main reason I wanted to include it is that it comes up in conversations regularly. I do have some friends living there but such things as schools has never come up as they don't have any children.
While there are some alternatives, most Gringos seem to head for the hills near David in the West end of the country. That means decent weather and relatively easy access to the beaches if they wish. Most of the population and most of the government is in Panama City. One of my friends told me it is a nine hour trip from where he lives to Panama City. Thus, if you need to interact with government, it is not very convenient.
The alternative would be to live in Panama City. But, like Managua, it is hot and crowded. Thus, like Nicaragua, good weather and urban areas are in different places. But, at least in Nicaragua, it is only a couple of hours from Estelí or Matagapla to Managua.