On the whole this was a lovely appartement, best suited for 4 people. Contrary to what we had imagined, we had in fact a small view on the sea. If you want to get to Fira by foot, it takes 45 minutes, and most of the walk is on the main road.
When we got to the airport, Giannis had arranged us a bus to come get us, which was 30 minutes late. Turns out the apartment was only a 2 minute drive from the airport, and we ended up paying 25€ for this very short trip in the bus. When we got to the apartment, our host explained to us very briefly where we are on a used map, and where to take the bus. To anyone who doesn't rent a car on Santorini, I highly suggest taking the bus, especially from the airport as you only pay 1.80€ instead of 25€ to get to the apartment.
The cleaning lady came everyday, and did a really great job at cleaning our rooms, so thank you!