Kardelens' apartment is fantastic ! Full of charm, with great arty deco and some very interesting books.
The place is very well equipped with plenty of handy bit and pieces for your stay (plug adaptors, maps, little guides etc).
The location is perfect, near the historical tower of galata and close to loads of tramway and subway lines.
Kardelen was very reactive and everything went smoothly the arrival and departure. I would come back without doubt.