My Parents and I spent a lovely week in Caroles flat.
Carole sent us directions from the station and then met us at the appartment to show us how everything worked. She also told us to ring her if we had any problems (luckily we didn't).
The flat was cleans and spacious enough for 3 people. We cooked in the well equiped kitchen each night and enjoyed the radio and the balcony.
The area is quiet and relaxed, with a great market twice a week and a lovely local bakery and butcher.
The metro is over the road, but we mostly used the bus to go into the centre from just outside the apartment (one goes to Opera via the Marais and the other to Gard du Nord).
I would certainly recommend Caroles apartment if you want to stay in a quiet area that is very easily accessible to nearly all of the main sites of Paris by Metro or bus.