We spent 5 nights in this appartment and would highly recommend it. It was very clean, equipped with everything you might need and just enough space for two people. The bed was very comfortable. The check in was very easy. The location is about 10 minutes footwalk away from Monastiraki square, where the Metro, Bars, Restaurants and Shops are located. The location is not the prettiest in Athens but it felt quiet and safe so I wouldn‘t see this as a problem. The view from the rooftop is amazing by day or night.
In conclusion I would say that this appartment is recommendable especially considering the low price. It is definitely worth it.