We had a wonderful time in David's apartment.
It is in a typical Parisian building and on the top floor so it has great views across the roof tops of Paris including the Sacre Coeur. The building has a lift and the apartment itself is very simply but stylishly furnished. It is located only a ten minute walk from Gare du Nord and just a stones throw from the Canal which is lovely to walk along. There are shops close by where you can pick up groceries etc. We also found a number of interesting and lovely vegetarian/vegan places to eat very nearby. It was very quiet in the flat also and we felt very comfortable and at home there.
David was a great host and although we did not meet him he left thorough instructions so that we were able to find the apartment and get in with no problems at all. He also responded almost immediately to any further questions we had about the apartment and the area.
We love going to Paris and would definitely come back to David's again - it is a great place to stay.