I just stayed with my family of five (three young adults children) at this perfectly located apartment and we did not have any space issues. Two full bedrooms and two full bathrooms + nice sofa bed were more than enough. A very well equipped kitchen helped to safe some time and money preparing our own meals a few times too. For those addicted to wifi and internet access, this apartment has fast and stable connection. For laundry needs, washing-dryer machine is at your disposal in one of the bathrooms.
Mehmet was as great as any host can get: he answered my inquiries within minutes (I am not exaggerating) and was on top of any concern I may have. He also runs a travel agency that can arrange transportation , guided tours, etc. (5 people is a tricky crowd to move in some cities as four is the max a cab can handle: he arranged a mini van to pick us at the airport).
For those considering this flat for a multiple day stay, I encourage not to get intimidated by the state of the sidewalks (terrible in all Athens!) or the graffiti on the walls: you will be surprised as how close the main attractions of the city are. you will forget them at soon as you enter the unit: modern and clean as it appears in the photos.
One important observation (just for those with mobility limitations or handicapped ): you need to walk up one leg of stairs from the street level to get to the “lobby” where a two-person elevator is available.