you might consider doing what we do, and you won't need a shuttle
Each year we do a circular five or six day route. One year out of Everglades City, and the next out of Flamingo.
Over a period of years, you can cover just about every part of the wilderness waterway, and then you can start taking off on other routes that get you into territory where you will never see another paddler during the whole trip.
The best part is you are saving that two hundred dollar shuttle fee.