Incredibly lovely apartment and congenial hostess. Travelers should consider an app such as Moovit which provides realtime bus info, very helpful moving around Bergamo and elsewhere. For instance, while in the foothills below Citta Alta you could use one bus (#1?) to reach the apartment, and then walk downhill. When departing, there is a different bus that you can reach by going downhill past the Art Museum.
But Bergamo should be visited; great little town.