My friend and I spent 4 nights in Dimitri’s apartment and decided to each have a short description, to be as accurate as possible. So here it goes:

1st Review
Pros:
Dimitris is a very nice person, he waited for us even though we arrived pretty late.
The studio is very close to the Agios Ioannis metro station (10 minute by foot) and you will get to the Acropolis in a 10 minute ride.
The neighbourhood is safe and, just opposite the Agios Ioannis metro station, you'll find a very nice cafe - it's called Cafe Cafe (purple walls outside), the people there treated us very well. We recommend it.
Cons:
The apartment is quite dusty and definitely needs heavy cleaning.
Although it has two beds, we only got sheets for one.
The street is very noisy both during the day and at night.

If you want to get fast to the most interesting sights in Athens and if you're willing to compromise on cleanness and quietness, Dimitris' apartment is a solution.

2nd Review
If this would have been my first Airbnb experience, I would have gone back to booking hotels. But luckily it wasn’t.
The place is plain dirty. The sofa sheets are dirty, the windows and window curtains are dirty, the fridge has a collection of past fingerprints, the few unpaired dishes left in the kitchen are dirty and the bathroom curtain probably takes the prize. I stopped pulling it because guess what… it was so dirty! There’s a lot of dust everywhere so we tried sleeping with the windows open. But then you hear the ‘noise’. Actually the streets around it are VERY noisy, especially if you are a person who needs good silence for a good sleep. At times it felt we were sleeping next to a highway. One of the broken windows mentioned below still didn’t get fixed so that added more to the frustration. The missing sheet that was mentioned by my friend appeared the second day – it was left on the door knob outside the place, just like that hanging, no bag no nothing.
The place is perfect for ‘what would I do with this place if it was mine’ game, for people that don’t bother so much with dust & noise, for people that look at location and price only.
And Dimitri is indeed a nice person but that’s just not enough for me. We didn’t really need help around so after the initial introductory evening there was no communication attempt on any side.
I would personally not recommend it, but hey… we also looked at 24 positive reviews and thought that the only one that had comments was a bit harsh… So it’s your choice :)
(2* - together)