Our hotel, according to Google street-view, is only a few steps from the Châtelet exit at Sainte-Opportune (the very one in the picture on the wiki https://fr.wikipedia.org/wiki/Ch%C3%A2telet_(m%C3%A9tro_de_Paris). How hard is it to find this exit once we have been deposited at Châtelet - Les Halles by RER B? (Is there a map of the stations anywhere online?)
My wife and I will be first time visitors to Paris (traveling with backpacks only). We were going to take a cab from CDG to our hotel but this website has me thinking we can save a few bucks (for some extra e'clairs) if we use RER B instead. I have a pretty good sense from Google maps how I would get to the hotel if I exit out Les Halles itself... but we are going over next month so I am thinking if the weather is really terrible when we arrive we might be better to be underground till the last second (at least till we can rinse away the 11 hour flight, etc).
Is the path to that exit well enough marked for a bleary-eyed Canadian first timer with only a bit of menu French?
Is it well marked and easy? I would say no.
Chatelet Les Halles is a very large station and has nearly a dozen exits. It'll be overwhelming at first, but it's doable, especially with backpacks which make the fare gates easier to manage.
There will be signage for Sainte-Opportune exit after leaving the RER B arrival platform in Chatelet Les Halles and you make your way up the escalators, but it may not be visible immediately. You may have to wander around looking for the signs pointing to that exit.
At worst you could exit at the closest visible exit and then find your way at street level, which will be easier since you can use Google Maps on your phone (download offline map area before you arrive in case you don't have data).