The flat is in the heart of Megalochori. It is far from Oia and Fira, but there is a bus stop a 5-10 minute walk away that will get you to these places. For me, the bus came often and was very easy to use. The little town is adorable and very small, with lots of restaurants to eat at, as well as a great gelato place. There is not too much within walking distance, except for an overlook maybe a 20 minute walk.
There is a horseback riding place about 5 minutes from the flat that is definitely worth looking into.
The flat was small, but perfect for 1-2 travellers. Very clean and modern, there is a fridge, a tv, and a little table and chairs to sit outside at and make some cat friends.