Christopher's place is very conveniently located near an international train station, a national train station, subway and bus stops. The neighbourhood is however peaceful and safe. It's also easy to walk to places of touristic interest.
The room is as described: not big, but enough for two people who want to explore the city and come back to the airbnb to get some sleep. If you are a light sleeper I'd bring earplugs: there is no sound insulation between rooms. With earplugs, I had a good night of sleep, though.
Sharing the toilets, shower and kitchen went smoothly. If you are looking for a inexpensive place that's well located, I'd recommend Christopher's! He and Elif were very helpful with check-in