Where did you say this 'great apartment in Paris' was?
Hmm... Perhaps this little map helps you to see a little clearer. Basically, it couldn't be better situated...
There's another métro station even closer than Etienne Marcel (line 4); it's Rambuteau (line 11). Plus Arts et Métiers station (lines 3 & 11) is two minutes' walk. Thre métro stations just nearby!
Rue Montmorency is a pretty quiet street as it is, but our apartment is on the courtyard. Ah, calm!Any other questions, give me a shout. ;-)