I plan to look how it is mapped on cadastre.bg, but the site is in maintenance so we have to wait a bit. I think the one building where you put the entrances is really 2 buildings: Аксаков 7 + Георги Бенковски 4. At the other end of the street, a building was tagged as Георги Бенковски 8 that looked like it is part of бул. Цар Освободител 8 so I changed the street tag. Those buildings should probably be merged.
I think normally we add the address to the building, not the entrance (but if a building has more than one entrance, we add ref=А, Б, В, etc. to the entrance).