Clean and very comfortable place. The location is on the street, but it's a wide boulevard (refreshing for Thessaloniki) and the windows do a great job isolating sound.
We had trouble with wifi and communication which is the reason for the 4 stars, as the process of getting the password was entirely too complicated even though we had previously stated we came there for work. (Waited 1hr to log in)
Otherwise, Kristina seems like a great host and I'm sure she'll change the listing and card info in the apartment itself to make matters easier.