In August 2023, we used Corfu Taxi Tours for our day in Corfu. It was a fantastic day and Spiros was an excellent guide and driver. He was very funny, accommodating and flexible in what we wanted to do, and there was a lovely snack stop that was so filling. This is the website and Spiros was very quick to reply. Spiros Kritikos - Unique Private Taxi Tours in Corfu (corfutaxitours.com)
For our stop in Argostoli we used Kefalonia Taxi Service. It is such a beautiful island. You must be sure to book a beach break, the water is out of this world. Be sure to bring flip flops though in case you end up at the beach with stones. Your feet will thank-you for it. The underground lake is also amazing. We used Kefalonia Taxi Service | The Local Premier Taxi Firm On the website for the premium tour which is what our group of 8 booked, it is impossible to do all those stops in 7 hours with the lunch break. We were cutting it close to get back to the ship and were a tad nervous. Also because it is very mountainous and lots of ups and downs driving and a lot of curvy roads, one of the people in the group did experience motion sickness so maybe have some motion sickness pills just in case. It is a gorgeous destination though.
Enjoy planning your adventure!