We are a couple from Valencia (Spain), we went to spend a few days in Athens at the end of January and we felt very comfortable in this apartment. It have a kitchen with everything you need to cook and a fridge, heating in the room and in the bathroom. The apartment had everything we needed and was in the center of the city (next to a metro stop and Acropolis). The area is safe and quiet.
Don't forget to take comfortable sneakers
to visit all the temples, monuments and museums! You will love it!
PS: University students of the European Union have free admission for all monuments and museums (or almost all)