Where to sleep in Dubrovnik depends on stairs, buses and your budget
Inside the Old Town is for a short, mostly car-free visit. You wake up close to the walls and can use the quiet early hours well, but many rooms mean steep steps, no doorstep parking and noise from restaurants or passers-by. It suits couples and first-time visitors who will spend most of their time behind the gates. Ask the host for the number of steps from the nearest taxi drop-off, not simply whether the property is "central".
Ploče makes the Old Town easy but is not automatically easy on foot. East of the walls, it is good for sea views and a quick approach to Ploče Gate. The trade-off is hillier terrain, so it can be awkward with heavy bags or limited mobility. Choose it for a short stay where you want views and do not mind a climb; check whether the advertised parking is actually available to guests.
Lapad works better for a longer break or beach time. It has more hotel stock, a promenade, swimming access and regular city-bus links, while the Old Town is a ride away rather than outside the door. Families and travellers who want pools, lifts and fewer stairs will usually find it less tiring. The downside is needing to time the bus or taxi when you return late.
Gruž is the practical ferry and bus base. Stay here if you are arriving by boat, taking day-trip buses, or prioritising a more functional arrival with luggage. It is not the postcard version of Dubrovnik, but it can be the right decision for a multi-stop itinerary. A car adds little value in the centre, so only book parking if you genuinely need it. Match the base to your sightseeing plan in things to do and the meal locations in where to eat.