Housing Unit Without a Window Facing the Public Domain

I live in a housing unit and I don't have a window facing the public domain, only a window into a space that ventilates the unit, but no one can see this window except the household members. Should I light at the window, on the table in the living room, at the entrance to the apartment in the stairwell, or at the entrance to the building visible from the street?

There is a dispute between Rashi and Tosafot regarding whether one can light at the entrance of the building. According to Halacha, the Shulchan Aruch ruled according to the opinion of Tosafot that one should light at the entrance of the courtyard [or in the common case, the entrance of the building]. However, the custom in practice is to prefer the window, according to the Biur Halacha and the Chazon Ish, who were concerned about Rashi's opinion. Therefore, one can light at the entrance of the building and thereby fulfill the opinion of Tosafot as ruled in the Shulchan Aruch. Nevertheless, one who wishes to be concerned about Rashi's opinion, as is the common custom today, should preferably light at the window, since even according to Tosafot, one fulfills the obligation post facto by lighting inside the house.

Shabbat (21b) dispute of Rashi (there s.v. mibachutz) and Tosafot (there s.v. mitzvah); Shulchan Aruch (Orach Chaim, Siman 671, Paragraph 5); Azmera Leshimcha Bulletin (Issue 117).