I did not get to meet Yiannis since he was on holiday himself but I did meet his mother and she was wonderful. She went and bought us juice, water, and milk just in case we wanted some for the couple days we were there.
The location is absolutely perfect. It is a 10 min walk to the acropolis and the cool restaurants and bars are a block away. The place is done up very well and has everything you need. The bed is extremely comfortable. I recommend this apartment!