Toll free route to Annecy

Hello again, Hopeing to pick some brains regarding our upcoming trip to Annecy. We have been looking at routes to get there with the viamichelin website but wondered if anyone has a tried and trusted route they could recommend. We don't mind taking extra time to get there as we want the travel to be part of the holiday. We haven't booked any pitches so are totally flexible. We worked out the toll fees and for our camper which would come under the class 2 vehicles it would be about £100 each way in tolls. This will be our first time in the camper to France and we want to enjoy as much of it as possible. Once we reach Annecy we hope to do a tour round the Alps. We have 17 days, going in May. Thanks