This was one of the most magical experiences we've ever been on.
My wife and I booked this excursion last week while on our honeymoon during a day trip to Capri (we were staying at Positano and took a ferry). It was just us and the skipper, a kind man named Cheerio. It really only did take about 2 hours so the timing was perfect. The boat could've easily fit another 2-3 people on there so we had plenty of room. We saw that there were some sodas and waters in the cabin below, which we think we could have had if we wanted, but we didn't want any. I'll also note that I had to change the time of our tour due to ferry schedules (I did this just over 24 hours before the scheduled time with no issues).
The weather was also perfect for us, and all throughout Italy actually, with the locals saying this was definitely more summer weather than they normally would expect for October, but we made the most of it! No clouds and perfect temperatures (65-73°F for the most part).
Our skipper for the day was great. Cheerio took our pictures at all the scenic locations I mention below and he pointed out all the big sights you can see from the island. Also, he was just a very kind and respectful man in general and that made the experience that much better! We didn't feel like someone was constantly "in our face" if that makes sense. It was very much just a trip for us alone. However, if you do want more of a "please tell me more about xyz sight" I'm fairly certain he'd do that if you asked. We just wanted more of a quiet romantic trip and that's what we got, with plenty of pictures along the way of course!
We toured all around the island starting first ,almost immediately
since it's close, with the Blue Grotto which I'll discuss in depth as it's the most popular attraction. I read a lot of reviews across the internet, and even here, saying you may end up turning away from the Grotto due to long wait times. We didn't have this problem at all. It was the last week of October, which is supposed to be the very last week of the tourist season, so maybe we were on the tail end of it? It still seemed pretty crowded everywhere we went in Italy on this trip so I don't know if that's the case. Or it could just be that it was the fact we pulled up in a private boat with only two of us? There were a number of other boats already there (some like ours and some much bigger with many people) and plenty of people waiting on line on the stairs coming via the land route as well. Maybe Cheerio just knew the guy who immediately came right to our boat when we got there to take us into the Grotto haha. Either way, it all worked out perfectly for us, and my wife even had time to change in the cabin on the boat beforehand. I'm pretty sure you can skip this whole part if you really wanted to though.
The Grotto costs €14 and the row boat skippers will expect and even ask for a tip on top of that. I'd say to just tip the row boat skipper at the end without issue. It's the very rare occasion you'll ever tip in Italy, so really not much to complain about. You need to lay fully down flat on your back in the row boat and the skipper has to pull the boat in via a chain, and the boat sort of submerges very slightly, but no you don't get wet. You're in the grotto for only some minutes, and there are other boats in there with yours. The skippers all sing inside with a sort of haunting echoing vibe, in part, but I also found it a bit funny and just a lot of fun since I already knew to expect that. Our row boat skipper took our picture inside as well.
Now I know what you're thinking, yes maybe this whole Blue Grotto thing might seem touristy to some, but really, when are you going to do something like this again? Just go all out and enjoy it. We did and it was a beautiful and fun time. Be aware that the sun is the reason the grotto is blue, so keep that in mind. If it's cloudy, you might not see the effect I've heard. We didn't have that issue though as I mentioned about the weather above.
After the Blue Grotto, we moved on and started our trip around other parts of the island which takes the bulk of the time. We went to the heart cave, the Saints Grotto, White Grotto, Natural Arch, and even swam through the Green Grotto from one side to the other while our boat met us on the other side. The Faraglioni rocks were awe inspiring and we went right under them in our boat too. All along the way you see these beautiful natural rock formations and hollows in the island as well as many of the famous picturesque buildings and hotels (and no there aren't actually that many of these so you will experience more of the beautiful nature than anything commercial).
My personal favorite highlights on the tour were swimming through the Green Grotto (seriously do it because it's this beautiful cave you go through and you can easily see fish under you with just your eyes; overall very magical and quiet) and then the Faraglioni rocks. I loved the rocks from a sort of monumental visual perspective probably most of all. Truly something you don't see too often on any given coast.
I'd recommend this tour to anyone, but especially couples just looking for a little quiet romantic trip and to escape from reality for a bit, even the reality of vacationing in crowded amalfi coast towns haha. There's something really special when it's just you and the person you care about most on a trip like this taking in some of the most beautiful sights nature has to offer.