My spouse and I did the "Amalfi Coast Full Day from Sorrento" tour, which we learned of from the Rick Steves Italy guidebook. https://www.sharedtours.com/
On-line signup and notification process was smooth. One can easily check to see how many people have signed up on specific days. (We signed up a year early. No others had signed up until a week before the tour.)
Many people had signed up for the same day as us, so we were divided into two groups travelling in separate vehicles. (We never encountered the other group). We were assigned to the smaller group, so traveled in a minivan with a single driver/guide. The other group was apparently in a small bus.
Our guide/driver was excellent. Vincenzo is an experienced and polished guide who was a pleasure to ride with. We tourists were 3 couples; my wife and I were lucky to have the front-most seat next to Vincenzo. The front center seat legroom was a bit cramped, but this was offset by the fantastic front-row view and close proximity to Vincenzo’s narration. (We offered to switch with the other two couples on the way back, but they preferred the rear seating.)
The tour was excellent and a great value. We really enjoyed the opportunity to visit and freely roam within the 3 towns. At Amalfi we ate at a small place named cuoppo d'Amalfi that deep-fried smelt and octopus (and other ingredients) on demand, and served it in a cone. Delicious! (Though the web site recommends bringing a snack, we didn't need one.)
This was a great way to experience the Amalfi Coast, avoiding the stress of driving and instead simply enjoying the scenery, free to independently explore three picturesque towns.