In short
Paros sits at the centre of the Cyclades and works as a ferry hub: from here, Naxos, Santorini, Mykonos and Amorgos are all reachable within the day. It is the most practical base in the archipelago.
Naoussa, a Venetian fishing port in the north, and Parikia, the main town, offer the same Cycladic setting as the famous islands, at rates that have not taken off in the same way.
What it really costs
The island costs about half of Mykonos and a third less than Santorini in high season, for scenery of the same kind.
Parian marble made its ancient fortune and the island is still lightly built outside the two ports. Renting inland, at Lefkes or Marpissa, brings the price down further.
What nobody tells you
Cycladic ferries are at the mercy of the meltemi: a strong wind cancels sailings, sometimes two days running. Leaving a margin before a return flight from Athens is not excessive caution.
Golden Beach and New Golden Beach, on the east side, are recognised windsurfing spots precisely because it blows there. Calm swimming is on the west.
There is no large town: in the evening, life concentrates on two ports. Anyone looking for a nightlife scene will find it in Mykonos, not here.