It is a really nice apartment! Very clean & you can feel that the owner loves his place.
Huge balcony is very romantic:)
I think it i one of the best variants value-for-money in Athens.
Some little things that were strange - the washing machine is locked literally by metal fence so you may use it only through the cleaning lady by leaving her your clothes once a week.
And though the house is among small streets it is still almost the center of the city and you can hear all the life that is going on outside - which is quite typical for Athens as I noticed during my 1.5 months stay.
You should also check the drainage in the bathtub - I'm sure it can be fixed within a day, I just had to leave earlier and didn't manage it but while taking a bath the water will fill half the bathtub and then slowly drain.
I would definitely recommend this apartment and would like to stay there again when/if I come to Athens again.