You don't want to stay too far from the center of Paris, especially to save $. You'll just end up spending it on transportantion.

I stayed at Hotel du Sejour - ADORABLE! affordable and in a great location.

http://www.tripadvisor.com/Hotel_Rev...de_France.html

http://plus.xdrive.com/u/37479721/56...21ukIEc1OiNna6

We stayed at du Danube last year and found it to be a good, comfortable hotel in a really terrific location. There is a cafe right next door for your morning croissant althought the hotel also offers breakfast. We traveled with our two daughters and found the 2 bedroom, one bath for 210 euros a night a good bargain. The staff was not overly friendly but were helpful in recommending restaurants, and even let me use the fax machine. We would stay here again.