Sorrento 4 nights October - Amalfi tours

Hi, Giangilberto from Milan, so the first aspect to take into consideration is the most important one, which month you want to come to Italy for your trip?
Because if it will be September or October the ferry schedules are already very limited like the SITA bus timetables.
It will be better to you to get a ferry instead of a bus, buses could also sold out, if a bus will be full of people they will skip the stop and go further.
To return you must do one fundamental thing: check the time of the last available journey because if that will be cancelled there are no other options unless you want to take a taxi and it will be expensive and you have to book it in advance.
For example Positano has a very small pier, it only accepts small boats and therefore in the worst case scenario in which there were to be rough seas the small boats are the ones that are cancelled first because they are not very stable and therefore.
What I feel like telling you is whether you can have dinner where you will then sleep or obviously as I told you before check the last journey before sitting down to eat.
If you want the sun during the day and dinner in a picturesque place in the evening, but these two things do not coincide, the return could be a problem.

In this area, it is nearly vital to eat where you sleep—you could pay for several dinners with what you’ll pay for a private transfer back to Sorrento as bus is almost sure to have stopped running at that hour.

You can take boat tours from Sorrento to the Amalfi Coast, but the one I took only gave us about 3 or 4 hours combined in Positano and Amalfi. I guess you could take the ferry from Sorrento to the AC on your own and maybe stretch it to 6-7 hours on your own. The coastline views are better, more panoramic from the ferry than the boat. From the boat, the views are also more likely to be obstructed by other passengers. But going on your own is riskier due to potential ferry cancellations. I don’t recommend either option. If the AC is a priority, stay on the AC.

I doubt there are any group tours of the AC that include time at a beach. But you don't make clear whether you want to swim on the vacation or on the daytrip/tour. Do you understand that Sorrento is built on a cliff and has vanishingly few beaches. Also, check October water temperature. Some famous towns, like Positano, only have pebble beaches, and they are rather small, compared to public beaches in the USA and the Caribbean.

https://seasonsyear.com/Italy/Positano

We spent five nights in Sorrento, because it has the best public transportation connections, and had a great time. But we did not go swimming even once. We ordered a car and driver (not a "guide") for 8 hours, to see the AC in comfort, and that worked well. But road traffic is a big factor. Our luxury clifftop hotel (Ambasciatori) had extensive, private, boardwalk (not "floating piers") areas for swimming, reached by the bottom button of the hotel elevator. I think the other four luxury hotels adjacent to it are like that too.

Just to be clear, I'm not condemning your ideas, or saying you've made a mistake. Rather, you need to do some more reading (for example, in the search box top left desktop view, often in blue) about the realities of this area. No question Sorrento has the most restaurant choice, and the longest restaurant season, in the area.

I found the Green Grotto (on the AC) to be a let-down. However, we skipped the Blue Grotto on our independent ferry day on Capri, as it is a notorious time-sucker, and we'd been to a similar grotto in Croatia on a previous tour.

Just want to chime in and say a small group tour of the Amalfi (we did a shared van through Mondo Tours), will take all day and will not include dinner or beach time (although we did have time for a quick coffee on the beach in Positano). And traffic will be awful.

We did not do a ferry/boat tour, so cannot advise.

Lots of shopping and picturesque wandering in Sorrento, for sure. We loved dinner at the Marina Grande, which is (ironically) the small fishing marina. Restaurants tend to have a direct connection with the fishing boats there. Nice view of all the boats, pretty walk down from the main square in Sorrento. Many other dining options in Sorrento, some with sea views, some not. Shopping in Sorrento is pretty much the same as along the Amalfi coast, but more extensive.

Highly recommend a food tour in Sorrento if that's your thing. We used Sorrento Food Tours.

I would do sunbathing and dining in Sorrento. We were there in July and found it very walkable. Shopping, dining, beach, availability of boat tours. For the Amalfi Coast, I highly recommend hiring a driver to take you where you want to go at your own pace. By the way, I have done Pompeii and Amalfi Coast in the same day, it's possible, but not if you want more time in Pompeii.