Zena gave clear instructions on how to find her apartment. I wasn't able to meet her but i did not have any difficulty checking in and out of her place.
The apartment is very near the Eiffel Tower. There is a bakery almost in front of the building where Zena's place is, plus a nearby grocery store. It is also close to 2 metro stations (dupleix and bir-hakeim) and a bus stop (bus line 42).