Romanos was extremely helpful and organised a taxi prior to arrival from the airport and back. He was always available when I had questions and offered lots of curated suggestions for bars, cafés and the like, we were never out of ideas for places to go.
The apartment itself is modern, clean and in a very central location, with all the major sites only a walk away (Acropolis, Agora etc). If you do need to use it the metro is close by. The lobby area also features a lift that is an experience in itself!
I would thoroughly recommend Romanos as a host and the apartment for your trip to Athens.