Originally Posted by
messifan
I use skype or I buy the international calling cards and use them from phone booths, which are EVERYWHERE, known as "locutorios"
If you know local people and want them to call you then you absolutely need a local sim card. Nobody will call your foreign number from a cellphone. Buying one is no more of a hassle than anywhere else (I've done it in a number of countries in different continents).
Prepaid minutes cost about 70-80 cents per minute and more importantly incoming calls and text messages are free (the caller pays).