Constantine was very accommodating, responsive, professional, and fun! We booked him for a half-day private tour of Athens. Prior to the tour, I had questions about buying entrance tickets to the Pantheon, Temple fo Zeus, etc. (since these are not included in the tour), and he responded promptly to my messages. I purchased skip-the-line tickets beforehand as he suggested. He also asked us to set time we wanted to start the tour, and picked us up on time (at 7:30 am) at Hotel Sofitel (next to Athens airport). Before heading out, he asked if we had particular preferences on sites we wanted to see and what route we wanted to take (highway vs scenic) going to the city proper. During the drive, he gave information on Athens and gave tidbits of history. Our first stop was the Acropolis, where he gave us instructions how to get to Pantheon and Acropolis museum, and where to meet him again once we were done. We spent 1.5 hours at the Pantheon and the Acropolis Museum, and we just sent him a message on Whats App once we were ready to meet at our pick up point. He then took us to the Temple of Zeus, Panatheneic stadium where he went down also to take photos of us, then drove around the city to see Syntagma square (where we watched the changing of the guards at the Parliament), Monastiraki square. We were done around past noon, and we wanted to do shopping around the area, planning initially to take a separate taxi or metro going back to Hotel Sofitel. He offered to wait for us to finish shopping and bring us back to the hotel (for an additional fee, since this was a change of route). The additional fee was minimal, and well-worth-it because it would have taken us about the same cost, and longer time to take public transportation back. We also left with him, small statues we bought from Acropolis, so we didn't have to carry those around while we shopped. We spent about 3 hours shopping and messaged him on Whats App when we were done, and he picked us up from our meeting point. We needed to buy extra luggage and he brought us to a shop on the way back to the hotel. We talked about several things like his life in Greece, his family, food, shopping, religion, etc, so the time in his car was never boring. His car was also very clean, with water bottles provided.
It was a great experience overall. This is the right tour if you have half-a-day to see Athens and have a few extra itineraries in mind. Five stars to Constantine for graciously accommodating our preferences!