I stayed at Themis' airbnb for a month, working remotely as a software engineer. Themis is an awesome host and I would 100% recommend booking his apartment for a long stay in Athens. The apartment is in a calm and safe neighborhood and well insulated.
The apartment has an excellent internet connection, over 80mbps. I didn't have to fall back on my LTE sim once. The 4k TV is also very recent and has a fast Chromecast built-in, perfect for mirroring chrome tabs or having youtube/netflix in the background while you work.
The apartment is about 7 minutes away from a Tram station, where you can catch the T4 or T5 to syntagma or the Edem beach, which are both about 20-25 away. It's very convenient to be straight in between the city center and the coastline.
The apartment is about 15 minutes away from the nearest Metro station.
You only have to carry a magnetic card, no heavy keys. This is perfect if you are active and like to go for a jog.
Thanks!