I was not able to find the phone number for Manolis when I arrived in Santorini so it's a good idea to get this number before you start the traveling.
I was not able to get in contact with Manolis at the arrival, so we asked the taxi driver to help us locate the apartmenet. We aware that you have to collect the key at to laundry. The staff in the laundry were not sure about the apartment and they were not very helpfull.
Once this is said, the apartment was very clean, cosy and the balcony gave a fantastic view of Fira. It's very centrally located and shops and restaurants are very close by. The bus station is 5 minutes walk from the apartment. Do not spend money on a taxi from the habour - it's much cheaper to jump on the local bus. And do not rent a car. The local busses drives to every location on Santorini.
Be aware that there's noise from the street in the apartment, especially from the donkey's that passes very early in the morning.