Andreas' apartment is easily a under 5-min walk from Syntagma station and has everything in the vicinity (eateries, bars, shopping and even a post office!). Great communication before and throughout our stay, he sent details in advance to make the check-in smooth and also gave prompt replies when we had questions on the tv wifi.
The shower was the star - strong water pressure and constant temperatures for chilly Oct, and the washer + dryer was helpful.
Definitely recommended to stay there for an easy exploring of Athens.