We stayed in the "modern flat" on Makrogianni just opposite the Acropolis Museum for 32 nights in October/November 2021. It turned out to be a wonderful home-away-from-home.
What was best about the apartment was 1) its location on Markogianni, a pedestrian street lined with cafes and restaurants. We hardly ever ventured more than a few steps from our front door when going out for lunch or dinner, 2) the fantastic "front seat" view of the Parthenon on the Acropolis which we could see from the living-dining room of the apartment and from the balcony, 3) the spacious and elegant living-dining room with lots of seating.
The other rooms included 1-1/2 bathrooms, a small kitchen, two small but comfortable bedrooms. There is a small washing machine but no dryer (think hanging clothing on the drying rack and waiting at least one day for it to dry). The small building elevator was rickety but did manage to get us up to the 5th floor apartment without incident.
If staying here, be sure to try Elaea Restaurant right next door to the entrance of the apartment building. We ate here six times during our stay. We also tried just about every other restaurant and cafe on Makrogianni plus the excellent Italian restaurant, Bel Paese (three visits) just around the corner from the apartment.