where should we rent a car?

It's a good strategy, but there can be some tradeoffs. I've reserved in Versailles, for example, hoping to avoid having to drive out of Paris. But the rental car agencies are some distance from the RER stations, so it was a hike with luggage. Suburban rental locations can involve their own traffic issues and limited hours of operation. You can explore options on www.autoeurope.com. Especially at the start of my trips, when I'm not used to driving in Europe, I try to rent from a location that is close to freeway access. The freeways (autoroutes, of course in France) are easy to drive and let you get accustomed to how your car operates. Then, you can exit and begin driving rural roads such as to Giverny. If you rent at the Gare d'Nord, you can drive a straight route to the Peripherique and from there be on your way toward Normandy.

Just had rental car nightmare. Rented at Gare de Lyon hoping to avoid traffic. We reserved mid sized car. Got there and we could only get a compact or 7 passenger van. What a hassle to say the least! So if you only need a compact, rent it anywhere...they have lots of them at every location. But anything other than that, you'll need to go to the airport. Orly would have been in our direction of travel. Traveling with
a group of 7 in 2 cars would have been a hassle trying to transport people and baggage to the rental location. Once we got the car, returned to the hotel to pick up people and luggage, it was a cinch leaving Paris with NUVI in hand! Now just have the hassle of contacting Auto Europe car rental company for a refund! Ended up renting from National..they had what we wanted, same price, no huge line of disgruntled people and at Gare de Lyon...

Teri has a very good point about renting at the larger agencies. We've had substitutions at small agencies, usually up-sizing. However, two years ago we were given a Fiat lemon at Orly, not a small agency. It was July and they claimed it was the only compact left in town. Parisians book a lot of cars for vacation. Another time a National agency, booked through Auto Europe, didn't have what we reserved. There was no problem getting a refund because we used Auto Europe which avocated for us. Auto Europe has gotten us refunds on charges several times. If CDG is on the way to Giverny, you should rent there. A GPS will get you out of the maze.

Last year we rented a car on line through Budget/Avis. We picked it up in Paris right at Les Sablons Metro station. It is outside the periphery of the city and easy access to the freeway while at the same time easy access from our hotel using the metro. Just exit the metro and cross the street and you're there. It was also easy to return the car, although the traffic entering the area around 10 - 11 am was more than we had expected and we barely made it back at the appointed time. After returning the car, easy to get the metro to the city and transfer to the train to the airport.

We picked up in Rouen on one trip, years ago and it worked pretty well. Last year on another trip we dropped off at Orly and it was a nightmare because there were no signs and we did not have a good enough map. We figured what could be easier than dropping off at an airport, but we ended up driving into Paris by mistake. Picking up there might not be bad, just make sure if you also plan to drop there have a really good map. Orly is south of Paris, you are going northwest, but the distances are not that far if you know where you are going (which we did not hence our travel nightmare). Ironically our last stop before dropping off the car was Giverny.