It's very difficult to find a place to leave luggage in Positano. The marina service charged us €10 per bag!! And we had one suitcase and two backpacks. Besides, the bags were under a parasol, outdoors, all day. Luckily we found La Caravella, where we were kindly attended to by a friendly grandmother who kept our bags in a cool place (we had food with us). At first we were very apprehensive because of the comments saying it was difficult to find, but one of the comments helped a lot in finding the place and it's very practical. Leaving the marina, just walk to the right, very close to the beach, where all those restaurants are. And after passing the terrace of the last restaurant, you can see a white gate. Next to that gate there are two semi-detached houses. Just enter that gate and turn right. You're right there. Then you just have to enter the PIN code that appears below the QR code you receive when you book. It saved our day!