I stayed in Karims flat for 2 month during a secondment. The apartment is modern and Karim is an excellent host. Always easy to get in touch with him and he is very eager to help with problems. He is also very flexible and accommodating. The location is fairly central but a little bit rougher than the posh neighbourhoods in Brussels. Karim put a description of the neighbourhood in the offer so just take a look. I did not have any problems though. The disadvantage of the flat is that you can hear the noise from the staircase quite clearly. With earplugs, however, this is not a problem.