Buses will take you to most villages of Ios and in the Summer time bus services are frequent. Next best choise is a taxi, which you can call ahead and arrange pick up from any remote part of the island.
If you would like to rent a car, your personal travel agent Stefanos can arrange it for you, as long as you have a driving license (the days when you could rent a car without a driving license in Greece are long gone..). Prices from €25 to €40 per day, depending on the car you choose. You can pick it up from the port as soon as you arrive and drop it off just before leaving again.
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