Several years ago, while I still had a high-ranking officer of the Costa Rica National Police (Costa Rica has no army) on
my mailing list, I was able to get most of my questions answered about gun ownership and retirement in Costa Rica, because my former teaching partner was considering the option.
You need to demonstrate a minimum income (which I don't recall) to move to Costa Rica as a "pensioner." You can also move there as an "investor," if you invest a minimum quantity (which I also no longer recall) in a business there. Firearm permits are granted routinely, normally for up to three firearms, but the judge can allow more, so long as you don't seek registration for a quantity larger than 1% of what is held in the armories of the National Police. You
cannot register anything that has ever been a machine gun, such as an AK-47, even if it has been rendered semi-auto.
If you wish to visit Costa Rica periodically and carry firearms while you are there, you can charter a business there, the business can purchase the firearms, and, as an officer of the corporation, you can lawfully carry them.
I was told that firearms are fairly expensive there (roughly twice MSRP in the US), due to high import duties, but, around the time I inquired about being able to import firearms from your own collection, my informant fell off the radar screen with multiple assignments on border-security operations.
Costa Rica is the most democratic and politically stable nation in Latin America and, as a Spanish-speaker, I might have given some thought to retiring there myself were it not for the fact that I do not enjoy tropical climates.
As to the crime picture, the reason my informant had made his initial contact with me is that he also operated a private training academy, most of whose clientele were private security officers, for which there was obviously a need.