Why would you want to rent a car in Messina? To save money because there are four of you? Not going to happen. Train, round-trip, to Taormina for four adults will be $41.50. A bus will be less than that. The car rental would be at least 3 times that amount.
Have you ever driven in Italy? Have you ever driven where two lane roads are probably 30% less in width than they are in the states? Do you realize that the roads are not well marked?
I can answer yes to all of these and can say that I have no desire to drive in Sicily. I am also somewhat fluent in written Italian and still have no desire to drive - I'll take the train.
There are a bunch of us on the same cruise that are going to do self-tours using the bus and/or trains in Messina. You do not want a car!!
Radiance of the Seas - Nov 2006
Legend of the Seas - Jun 2007
Costa Fortuna - Mar 2008
Legend of the Seas - Oct 2008
Celebrity Constellation - July 2009
MSC Orchestra - Jan 2009
Navigator of the Seas - March 2009
MSC Poesia - November 2009
Jewel of the Seas - June 2010