I have been staying in this apartment for more than 3 weeks. Here are my empirical tips:
1) the apartment is near Tunis train station (6 minutes by walk), and metro of Barcelona Place stop (6 minutes by walk). But several locals warned me that the location is not safe at night, largely because it is at the end of Carthage street, being located at a crossing. During my staying, I rarely went outside at night, except with local's company.
2) Noisy from 5:00 a.m. until 23:00 p.m. It is also exactly the place for public transportation station (mini bus)--vehicles' noises, dog barking (in the middle of night), and mini bus drivers' crying out for passengers.
3) in this apartment, no hot water, no internet (not even to mention Wifi). The fridge also didn't work. On the day of check-in, Imen send her friend to give me the key, when her friend tried to solve the problem of no hot water for taking a shower. But failed.
4) Saavy neighbor. I never brought male to this apartment during my staying--in most of the Arab countries, it is a taboo. But one night, the neighbor, who's house is just opposite to this apartment, waited for me until I came back from the train station at 23:30p.m. She said, "all the neighbors in this building heard sounds of both man and women in your house." With continuation of our conversation in Arabic, I realized that she fabricated this mixed gender under one roof, intending to implicitly threaten me, so that I could follow her order to remove a mattress which is likely to be put outside in the communal area of the same floor by the owner of the apartment that I was living. Neighbors could make trouble to foreign tourists.
5) I explored Tunis alone, going out to the restaurant to try local food, making new friends with locals, being invited to join their Eid-- I think all these is largely because I speak both Modern Standard Arabic and some North African dialects). But no practical suggestions, help, introduction from the owner of this apartment -- according to what I know from the neighbors, they have moved. I even did not see them. So, this apartment does not fit Airbnb's theme at all (at least during my staying period). In Tunisia, Arabic and French are widely spoken, but not English.
6) in the first few times when I approached Imen for possibility of living in this apartment, she replied message quickly (from within half an hour to within one day). But since my payment has been transferred, late reply--usually within 2-3 days.
I hope these are helpful for you if you are considering living in this place.