Best answer is to look on the website for the part of the forest you are visiting. Some are a first come basis--no fee and primitive camping, some can be reserved, some have hook ups and that will cost. Check the website fir the Sawtooth National Forest and select the part of the mountains you plan to visit.
As I remember, most campsites are regulated on an Honor Pay system. Where ever you go you should Expect to Pay something, since Someone has to Maintain the camp!
Some campgrounds are but most have a fee
It's a free country sleeping on the ground shouldn't cost u money. .
There are both. There are some improved camp sites for campers as well as tents that require a fee, some are best to make reservations. There is also spots without restrooms for more primative camping. You might want to decide what your wants and needs are and then contact the National Forest Service for information and travel maps.
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