Need help in figuring out what can be done to use my US bought phone as a local international phone in Costa Rica. 1- Does my US phone need to be unlocked, and how is that done without voiding its warranty? 2- Can I just replace my US Verizon SIM with a local Costa Rican SIM? Is that all I need to do? 3- What else do I need to know about making my phone into a true international phone? 4 -There has got to be a better option than buying or renting another international phone or using my current US phone and settling for Verizon's very expensive service solution? 5- Is there an existing thread or discussion that covers any or all of these questions? Where is that info?