A private pilot may fly the helicopter with few restrictions, as long as they are not providing services for hire.

With just a private pilot certificate, the pilot may operate in all airspaces with an aircraft less than 12,500lbs, excluding Class A which requires an IFR rating.  With a few exceptions, the pilot may not be compensated for the flight.  The pilot may be reimbursed for the pro-rata share of expenses of other passengers.  A pilot may act as the pilot in command for a business if the flight is incidental to the business and the flight does not carry passenger or property for compensation.  There are a few exceptions, such as providing flights for charitable organizations, search and rescue operations, test flights, and glider towing.

Reference(s):

14 CFR 61.113 – Private pilot privileges and limitations

Other Pilot Certificate Items