You need a recreation passport, which you can get if you are a Michigan resident when you renew your license plate, or you can purchase at the park entrance.
It is a State Park so unless it has a different policy you either need the sticker or have to pay the entrance fee.
No, it's free.
From May-September you do. October on you do not need one.
Yes you need the park pass
Yes, but you can purchase the stickers there.
Yes
Yes. There is also a parking lot outside of the entrance, right by the beach, that is free.
Yes, or you can purchase a day pass
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