Welcome to Nicaragua!
Frankly, I spent some time in Costa Rica back in the mid 1990's when the crime rate was a lot lower than it is now, but even then, I was always a target for scams, by the locals. The home that I rented was burglarized within the first month of my arrival, and generally, I felt that my wife and I were not welcome there.
I go to back to Costa Rica several times per year to visit family there, and always enjoy my time, but now with all of the drug traffic, and street crime, it has become a pretty sketchy place to be for anyone who is concerned with personal safety. Also, the many of the locals there are among the most arrogant, rude people that I have encountered in my travels. There are, however, many fine people in the country, and some of my best friends are Ticos. With that being said, and taking into account the ridiculous prices there, it is not a country which I would choose for an extended stay.
Nicaragua, however, is not only the safest country in Central America, but one of the friendliest countries to which I have ever traveled. Do your homework. Come and stay for a few weeks. Look around, and simply live the life here. Nicaragua is not for everyone, but it just might be for you!
Best of luck!