The flat is very nice and cosy. There is a big terrace with lot of space. City center is approximately 20-30 min of walk. U can use bus (2 or 11) from/to the center. Nearest metro station is cca 20 min walk away. If you don’t want to walk, you can use uber.
Every Tuesday there is a market in the next street with lot of goods. Virginia is nice and owner ready to help when you need.
If you are longer in Athen, I recommend you also a trip to Delphi and Aegina island.