It's an amazingly beautiful apartment near pretty much everything you need in Athens. I can recommend it to everybody visiting this beautiful city in Greece!
Location:
We used to walk daily from the apartment to Monastiraki Metro Station and it's really no big deal (like 10min or so). There are several restaurants and mini markets (some open till 24:00, some around the clock) nearby (5min walk) and even though the area might seem shady to some western europeans like we are, it's actually not. I had no reason to fear even though I walked this street after midnight. The only thing that might get you in Athens are the pickpockets and tourist traps (putting bracelets on you and THEN requesting money,...).
Apartment:
Clean, has AC and is beautifully designed. Also the doors are security doors (full metal frame, 8 thick pins) which definitely ensures nobody gets in without the key. You can cook, wash and have a fridge. Also there are a lot of things you can definitely need if you forgot to bring it yourself (Shampoo, Towels, Blankets, band aids,...). The price we payed was definitely cheap in comparison to other western european countries.