The check in/out process was fast and easy. The apartment is located 7 blocks away from the Omonia station, so get the Airport from the apt is straightforward. Crossing the Tsaldari street there are a lot of pubs, bars, restaurants, etc, with an amazing night life.
We felt very comfortable in the apt, we used to had breakfast in the balcony which is full of plants. We stayed in Carlos apt during mid summer, so both AA were essential and helped us to have good rest in the night.
The neighborhood is not the best but I do not believe is unsafe.