Marc's apartment is in a perfect location very near the Eiffel Tower. Combined with a Velib pass, it's everything you need to make the most of Paris.
Be aware that is in on the 5th floor so make sure you can carry your bags up and down that many flights of stairs. The setup is a little unusual (kitchen and bathroom are in their own rooms outside the apartment) but we didn't do a lot of cooking so it didn't bother us.
The place had an unfortunate smell similar to blue cheese or a good local Camembert - we're not sure if it came from the building, the neighbors, or the apartment itself but it took some getting used to and seemed to grow stronger in the afternoons.