First, I was staying at an AirBnb and the company arranged a pickup at a motel close to me, going the extra mile. Sheldon, our guide, was friendly and prompt and REALLY went the extra mile to let me move my car to a close public lot since I was concerned about being towed...huge appreciation there!
There were nine of us in our group, "our family" for the day, and it was a blast. Sheldon provided all the info we could possibly want to know about things along our route, at our first location through our final drop off. We stopped for scenic views, to walk on lava fields, six points in the canyon, incredible lunch at the Cameron, and a nice little stop to explore at the Village, especially the El Tovar which is so pretty.
Sheldon is passionate about the GC; I asked if he ever got tired of seeing it; his response "Never". There were so many "little" things a person on his own would miss, like "step over here for the view of (fill in the blank). The spirituality of the entire place is so evident; an experience not to be missed. If I am fortunate to be back in the area, I will definitely go with this company again and hopefully get Sheldon as the guide.
You won't regret making the decision for a tour, especially if you are a first time visitor.