Elelven of us arrived in Santorini having organised a minibus to take us to Oia for the afternoon, but once we arrived we found that we had to wait ages for the tender to take us to shore, and when we did arrive there were terrible crowds waiting at the bottom of the cliff for the cable cars to take us to the top to our minibus. We were about to give up and go back to our cruise ship, when one of our friends spoke to a gentleman who was willing to take us by boat to Oia at a minimal cost.
I wish we had the knowledge to have done this in the first place. The gentleman's name was Anemos and we had a fantastic boat ride to Oia. Once we were there, we didn't feel like walking to the top, and managed to grab a minibus to the top, We had arranged for Anemos to collect us and he picked us up at exactly the time we asked him to. I would really recommend this boat trip to anyone who is in Santorini for the day!! I do hope that this will be helpful to anyone who wishes to save themselves some money rather than book an expensive a cruise tour.