Aristotelis apartment is in a great location (our family of 4 with 2 kids walked to the all the main attractions - Acropolis, Ancient Agora, Olympian Zeus, Panathenaic stadium within 20 min). The apartment was clean, the check in process was smooth (communication before arrival was prompt and the host met us at the door). It was easy to get a cab to/ from the apartment or take the bus (Syntagma Square is literally a 5 min walk) and there are plenty of restaurants and grocery stores within 5-10 min walk.
Aristotelis left some bottled water, fruit, cookies and candy for our family and walked us through the local map and our plans for sightseeing. The bed was comfortable (better than some chain hotels), and the 2 bathrooms helped us save time getting ready in the morning.
However, taking back to back showers is not possible as the hot water is limited by the size of the hot water heater (only 2 short showers possible). After the first day we were able to finesse the issue without much discomfort. The only other negative we encountered was noise at night (midnight to 2 am due to Carnivale supposedly) as the apartment only has single pane windows.
All said and done, Aristotelis apartment is in a great location and he is a great host. I would recommend staying in his apartment.