We've dropped off in Paris only twice. Once was near the Peripherique and it was very confusing and

Let's say we're picking the car up at CDG, driving to and then spending a week in the Brittany region and then dropping it back off in Paris. We're staying for a few nights in Paris and it seems to me that driving it to the airport is just a hassle. I believe we'll be staying in an apartment in the 6th arrondissement.
I think we'll be coming into Paris from Chartres. It seems like one of the more outlying offices (if open on a weekend when we'll be dropping off) would be less confusing traffic-wise and then we would take the Metro to the apartment.
You do not rent from AutoEurope: You rent THROUGH them. If you are picking up at CDG, you have to drop off at an office of the company you rent from. They may have an office near your Paris destination. Or not.
We've dropped off in Paris only twice. Once was near the Peripherique and it was very confusing and daunting. The roads were huge, the distances -- once we dropped off the car and were lumbered with our luggage -- seemed Gargantuan.
yes-- we have dropped off and then trained in. you should look online at a website like autoeurope, where they have a link to a map for each rental company choice. or you can call a car rental place, like hertz, and ask which is closest to a train station. car rental dublin ireland pick a place you are comfortable taking a train into paris from and that has a car rental place right at or near the station. then doublecheck that the rates are decent for that dropoff point. (they really vary) we have used kemwel in the past (all cars with zero deductible) and really like them-- they will match any price you can find and have been very patient with us over the phone. let us all know what you decide! car rental dublin ireland kawh
Driving INTO Paris as suggested above is not terribly daunting... don't forget you will have had a week of driving experience in France. Plan your route into Paris and avoid rush hour and you'll be fine.
Montparnasse makes sense. If that's what you decide come back here and you can get exact directions as to where the garage car rental dublin ireland entrance is. The signs indicating the entrances can be hard to spot... Streetview can really help with this.