Our group will be staying in Praiano in May for a week and will want to explore many of the wonderful destinations in the area, including Capri, Pompeii, and Paestum. We are wondering about transportation connections from there, as we will not have a car. It looks like getting around from there may be a bit complicated and time consuming and we are considering changing our home base to Sorrento. And advice is much appreciated.
The SITA bus stops at Praiano ; so you really do not need a car.
The bus travels back and forth constantly between Amalfi and Sorrento and Praino is along the route and a stop.
Praiano is a tiny place so changes are your lodging is close to the bus stop but something I would double check on personally.
No ferry stops in Praiano to my knowledge so the bus will be your main means of transport.
One word of caution, you will probably be fine in May ; certain times of year the buses can be often filled. If a bus is full it won't stop at Praiano to let more passengers on.
To get to Capri you would take the bus to Positano and then a ferry from there to Capri.
To Pompeii or Paestum without a car or tour is a little better but still can be reached via public transit.
Paestum, take the SITA bus to Amalfi and from Amalfi catch a bus to Salerno from Salerno I know you can easily reach Paestum but not certain if that is via bus or train from Salerno.
There is also a ferry Positano to Salerno as another option but check to make sure that is running in May
For Pompeii, have to catch the same SITA bus to Sorrento ; than go from the bus to the train and take a train from Sorrento to Pompeii.