A great place in the city center- close to all historical sites. Two beautiful terraces, the apartment is amazing really and the hosts are very welcoming and supportive.
Next to the building you have a specialty coffee place that I recommend - Valenio, as well as a place to eat (offers salads and a range of sandwiches, eggs, English breakfast, etc.) - Pastaflora Darling Cafe.
I highly recommend the Upper town walking tour. Mind you there’s a lot of walking in the hilly uptown, but it is more than worth it. Not only you are going to learn more about Thessaloniki, but also about the history of Greece and what events have shaped the locals over the centuries: thessalonikifreewalks.com.