I Finally booked my rental car for my France trip, but after even more searching i found a better deal than the expedia one. i went direct, and got it through hertz.com which has an office right next to the rouen train station [which is how i'm going to be arriving from paris]. this will simplify things and let me not have to talk in french just a little less. so while the expedia price was $181 for the four days, hertz direct was around $145 for the same amount of time.
Here is our current route map with a hot Opel Corsa [with manual transmission and no A/C - sweeeet!]