Hi, first time traveling to Italy. Plan is to spend 4-5 days in Rome then head to the coast for 4-5 days. Trying to decide where to stay, mobility is an issue so need to be near/have the option for taxis/ferry/some way to navigate the steep terrain. Thank you
I can speak to Sorrento, having just been there.
It's well connected, pretty flat, a compact historic tourist zone, large enough to have lots of lodging and food choices.
The ferry pier is a bit of a walk on flat terrain (split by an elevator ride) or you'd have a taxi deliver you to the Marina Piccola parking lot.
With your mobility concerns, I'd definitely skip Capri and Positano. Positano is generally a vertical town - mostly uphill - and Capri, while enough of it is pretty flat, is largely pedestrianized so you really need to be able to easily walk to get around. Taxis (which are expensive and have limited routes) simply can't get you from all points to others. Sorrento will be your best bet.
Capri also has a bus, but it can be very crowded and you might be standing. It's a 12 passenger bus and the first ride I counted 24 people plus a dog. My wife and I have always maintained that we'll take Capri over the Amalfi Coast anytime. However if sites like Pompeii are also on your list (mobility challenge alert) then Sorrento makes more sense.
Right: Capri does have bus service but limited routes and, as Allan said, they can be very busy/crowded. As he did, we enjoyed our 2-night stay on the island but it's very much a pedestrian destination. Luggage, if unable to carry it yourselves very far, has to be portered to many of the hotels for a fee from the port.