Villa River is a beautiful house with a large garden. Photos and description don't give the appropriate view. You will find two bathrooms with toilets, a dishwasher, a washing machine. Two days after our arrival, someone came to clean the house, change towels and sheets.
It is ideally located in a quiet location at a walking distance (10-15 minutes) from Kamares port. Quite convenient to take the boat. The beach is nice with a lot of restaurants on each part of it. This is the perfect location to enjoy the sunset on the sea (not from the house but from different bars and restaurants, or the monastery on the hill).
It is not easy to find the first time but someone was waiting for us at the port to pick up us to the house.
Sifnos is a very nice island, not too big, with some very nice beaches (I recommend the small one close to chrisopigi monastery, and Faros or Vathy)