Christos apartment was great! It looks exactly like on the pictures. It replied to all our needs in terms of location, friendliness of the owner, super great communication with the owner (rapidity, super tips, helpful).
It is simply furnished but had everything we needed. The apartment is located about 5-7 minutes walk from the sea front promenade (no beaches directly in Thessaloniki, the closest beaches are abt 25mn drive); the neighborhood has it all, from supermarket, to coffees, to small restaurants; the street it is located into opens up on the main streets. There is a weekly market in the parallel street on Fridays; Parking is hard overall in Thessaloniki but we always ended up finding a spot around the apartment.
The main city center is located about 20/25mn walk from the apartment but it is all the same city, so you can either walk along the promenade or through various lively neighborhoods. I would recommend!!