Hi there, both locations are accessible (and cost effective) via the Italian train system, for Rome there is a frequent service to/from Civitavecchia plus a short walk at either end. Florence (Firenze) is a little less easy as you may have to change in Pisa, and the train station in Livorno where the ship will dock is a good couple of miles away - there is a regular bus service to the shuttle pickup/dropoff point.
An alternative is to get a group of you in a taxi, but make sure you negotiate the price before setting off.
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