The unit was up 2 flights of stairs with no elevator (as noted in the listing). It was clean and spacious and tastefully decorated. The radiator worked well and kept the unit warm all night. The bathroom was exactly as expected with a tiny tiny little sink, be careful when using it or you might miss the sink bowl when you're brushing your teeth!
The location was excellent and very close to the center of Brussels. There are many eateries and bars and coffee shops nearby, and less than a 15 minute walk from the main station.
In summary, I would come back to this unit.