We really enjoyed our stay at Zain's place. The location is very central, so close to Syntagma, Plaka and the shopping street with lots of restaurants nearby and easy access to public transport. The apartment had everything we needed and it was spacious for the 4 of us (2 adults and 2 teenage boys. There is a mini shop just downstairs for daily needs and along the street many other shops (I particularly enjoyed the wine shop 300m down the street).
Zain was helpful when we had any issues.