Salerno to Positano, takes about 1:15 hours on the fast ferry.<,

And if miss the last ferry much longer by road perhaps - a few years back friends detrained at Salerno and took Amalfi buses to Amalfi but there was a landslide closing main coastal road and necessitating a long detour. Get that ferry if possible.

Shellie beat me to it, but yes, Palazzo Ravissa does have easily accessible parking, but do let know them know you will be needing it. And it is a lovely hotel.