Ici c'est bien expliqué pour différents types de logements ...en anglais:
http://wikitravel.org/en/ChinaLow-cost options
Massage shops, saunas, and spas: spa costs vary but can be as low as ¥25. Entering a spa very late at night (after 1:00 AM) and leaving before noon may get you a 50% discount. When in the spa there are beds or reclining couches in addition to showers, saunas etc. Admission to a spa is typically for 24 hours, and a small locker is provided for bags and personal possessions. This is ideal if you are traveling light. Furthermore spas often provide complimentary food, and paid services such as massages and body scrubbing. There is no privacy because usually everyone sleeps in one room. However, there is more security than in a dorm, since there are attendants who watch over the area, and your belongings (even your clothes!) are stored away in the lockers. Don't be fooled when receptionists try to make up reasons why you have to pay more than the listed rate. They may try to convince you that the listed rates are only for members, locals, women, men, or include only one part of the spa (i.e. shower, but no bed/couch). To verify any claims, strike up a conversation with a local a good distance away from the spa and inquire about the prices. Don't let them know that you are checking the spa's claims. Just act as if you are thinking about going there if the price is good. If they know that the spa is trying to overcharge you, they will typically support the spa's claim.
«Pourquoi voyageons-nous? Afin de rencontrer des êtres
qui ne s'imaginent pas nous connaître une fois pour toute » Max FRISCH
«Le véritable voyage de découverte ne consiste pas à chercher de nouveaux paysages... mais à avoir de nouveaux yeux» Marcel PROUST
