There is a laundry nearby at 37, rue de Trévise ([https://maps.google.com/maps?saddr=16+Boulevard+Montmartre,+75009+Paris,+France&daddr=37+Rue+de+Tr%C3%A9vise,+75009+Paris,+France&ie=UTF8&dirflg=w directions from office]). It's mostly self-explanatory (and has good english signage). The one thing that is unlabeled is the detergent/softener dispensing machine. In France, laundry detergent is generally (as it is at this laundromat) in small foil-covered bricks. The packets are something else (probably softener, maybe bleach). The money input for all the machines the laundromat takes either coins or bills.