How much is the renta cabins

https://www.state.nj.us/dep/parksandforests/parks/parvin.html

Cabins: 18 cabins each with furnished living room with a fireplace or woodburning stove; outdoor campfire rings; two bedrooms to accommodate 4 people; kitchen with running water, electric stove, refrigerator; bathroom with sink, toilet and shower; electricity; brick patio with table and grill. Two of the cabins are accessible for persons with disabilities and offer accommodations for 6 people. Playground available. Cabins are located on the north shore of Thundergust Lake. Cabins are available for rental for a 7 night minimum from Memorial Day to Labor Day. Open April 1 through October 31. Fee: Four-bunk cabins: NJ Resident: $55 per night; $385 per week; Non Resident: $65 per night; $455 per week. Fee: Six-bunk cabins: NJ Resident: $75 per night; $525 per week; Non Resident: $85 per night; $595 per week.

They are usually pretty cheap but definitely call and ask.

Depending on season prices vary