Dimitris was a great host, very communicative, and went above and beyond when our flights were delayed. The apartment is in a great location in the historic old city which is much more tranquil with some fantastic local restaurants.
Unfortunately, when we first booked the apartment it was advertised as a 'luxury' apartment. While it is adequate, functional, and comfortable, it definitely does not qualify as 'luxury'. The apartment has been renovated, but not to a high standard and the appointments and furnishings are a bit tired. (We've noticed the listing has since been changed to say 'chic' instead, which is still a stretch.)
Other things to note - the tenants who live upstairs are LOUD. Despite the advertised 'quiet hours', almost every day and night we were disturbed by loud voices, and the constant dragging of furniture directly above the bedroom at all hours of the night. This had a big impact on our stay and something that should seriously be taken into account if you're considering this apartment.
Also note that the listing advertises two queen size beds. This is inaccurate. Only one is a queen size, the other is a small double (and unfortunately is in the only bedroom with aircon).
We love Thessaloniki, but we definitely would not return to this apartment, especially for the price.