The car rental procedures are pretty standard with only a few differences between countries. In Greece you only need to show a valid US or Canadian license and generally need a credit card (just like at home). It always pays to check on-line before you leave home since most of the time you can reserve a car with no obligation. On some of the Greek Islands like Santorini, there are quite a few small local rental car companies that often have better prices than the majors. On Mykonos we generally do not recommend renting a car because there is not much to see on the island. If you want to go to a beach we usually suggest just taking the local bus to Paradise Beach. You also need to be aware that most of the cars rented in Europe are small and have manual transmissions. Automatics, if available, generally cost a lot more money (sometimes double the price).