Any number of cars are allowed but each vehicle has to purchase a $7 per day state park pass. Also, most sites only have room for one to two cars.
I know some sites are two tents and one vehicle, they also offer walk in sites not far from a small parking area in the back of the grounds. There are also RV sites with a power outlet along with some vehicle/ tent sites with power. As far as i know for tent sites though it one vehicle per site but they have a large parking lot in the front of the grounds other vehicles could park.
1-2 depending on the site
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