We have spent two days at Andrea's. The appartment is perfect, stylish, full of personal details. Andreas was an excellent host at all moments. He gave us directions and waited for us downstairs. He offered tips for things to do around the area and had maps and brochures at our disposal. The place is extremly clean, an oasis in the middle of Exarcheia. The air-conditioning in the living-room and the fan in the bedroom are great in the summer.
Exarchia square can be rough sometimes, but if you are aware of this, the area is central and convinient, and a city itself within Athens.
I fully recommend it.