N.H. Rev. Stat. Ann. § 216-I:7

Any property left in a recreational campground or camping park after check-out time or eviction pursuant to RSA 216-I:6 shall be considered abandoned. Such abandoned property may then be moved off the campsite and placed in storage. Any owner or operator or their agent of a recreational campground or camping park shall have a lien upon such property, so long as it shall remain in their possession, for proper charges due them for the storage and care of the property.