Affordable Paris: 17 Hotels. This article by Travel & Leisure is a decade old, but the hotels are still reasonably priced by comparison. We've stayed at Hôtel Le Ste.-Beuve in Montparnasse once before.
The first hotel I ever stayed in in Paris - here you'll have a charming, cozy, quiet, and affordable stay, proximity to several of Paris' best sights and things to do, and if you're lucky as I was, a view like this.
Hostels have a reputation for being party places filled with 20 year old students, grungy shared bathrooms and crowded dorms. But things have changed. Some hostels now rival nice hotels for amenities and cleanliness, and many have private rooms and bathrooms for couples and families.