Absolutely incredible location! We (family of 4) enjoyed our stay thoroughly. Marianna and her daughter welcomed us personally with great warmth, and are responsive and attentive hosts (thank you for stocking the refrigerator with milk, cheese and raki!). The house is almost literally the last one on this side of Naxos island, right in front of the beach, giving it a lovely remote "living at the edge of the world" feel. We enjoyed the sunsets every evening -- it was a truly healing experience :) There was a mini-market about 100 metres away that had almost everything we needed in stock to cook up dinners, though there are tavernas nearby. Close to other beaches as well. A real haven.
Note: Agiassos is quite far (30 km / 30 minutes drive) from the port town of Naxos / Chora. In order to get there, recommend renting a car, which is also useful for exploring other parts of the island. There is an uneven rocky/unpaved road at the last stretch leading to the house that might prove difficult for scooters. Taxi drivers wanted to charge us 60 euros to drive from the port to Agiassos :/ so renting a car proved to be the best option, though YMMV.