There is an outfitter on the Poudre in North Fort Collins called Rocky Mountain Adventures that will rent you everything to boat the Poudre. The trip from Estes to RMA is almost 90 minutes and then another 25 to the whitewater sections of the Poudre. During the summer hitching the shuttle on the Poudre is not problem and there is even a restauant/bar/roadhouse music venue called the Mishawaka Inn whereyou can grab lunch and launch for a class three section.
For easy IIIs you want to run the Filter Plant section that has a few riffles and only one real rapid. The next step up is upriver above a diversion dam (you can't run both sections together) called Lower Bridges, this is a solid III. Above Lower Bridges is the Poudre Park section which is class IV, then above that is the Lower Mish section which is class III.
The road runs along the river very much like the Nantahala and the Ocoee so you can access the different sections very easily and sort of jump on and off for the sections you feel comfortable with.
RMA has an office in Estes where they book rafting trips and fly fishing guides and they can take care of you.
If you want to bring the family rafting Rapid Transit busses people from Estes to the rier and back, that may be easier.
Messaage me through the Buzz if you have any other questions.