My family (Grandparents, mom and dad and two boys 18/15) had a great day in Guernsey with our fantastic tour guide Amanda Johns. Amanda and I corresponded well before the cruise and she helped me reserve a six passenger vehicle and driver named Andy (Car was very clean and Andy was a true professional) to get us around the island as she explained the history beginning with the beautiful port and continuing to the little chapel and everywhere in between.
Amanda worked with us to set up an itinerary that met everyone's interests and got us to all the places we wanted to visit. She also adjusted our meeting time so that we were sure to stay ahead of the tour buses that clutter up the smaller sites. We visited the Occupation Museum, the Underground Hospital site, the sites from the Guernsey Literary and Potato Peel Pie Society novel, little chapel and several other sites.
I would strongly recommend Amanda and toursofguernsey.com to anyone visiting the island, she is top notch!