I can highly recommend "Rome in Limo" to book tours at any ports in Italy.
We used them in Livorno to take us to the Tower of Pisa and then onto the town of Lucca where my DH and son played a round of disc golf on a local course overlooking the scenery. We finished the day with lunch at a local restaurant in Lucca before heading back to port.
We also used them in Rome and in Naples. In Naples, we arranged for a tour guide at Pompeii which added so much to our experience- she had a 3 ring binder to show us comparison pictures to understand what each building was like back in the day. We also toured Positano and the Amalfi coast with our driver- spectacular.
They do an amazing job customizing your day to fit your interests and stay ahead/away from the crowds. Our party consisted of myself, DH and our 12 yr old son, and we were able to take breaks throughout the days to grab gelato and drinks as we pleased.