The provision of subsection 76-290(b) of this chapter shall not be applicable to any person operating a tow vehicle
under the terms of a written contract for a specific period of time with any person,
firm or corporation to tow, transport, convey or move vehicles owned, controlled or
in the custody of such person, firm or corporation to a specific location so designated,
for consideration set forth in such contract; provided that the said person has in
their possession at all times while towing, transporting, conveying or moving any
such vehicle, such contract or an affidavit which shall recite the existence of the
said contract, the name, address and phone number of the contracting parties, the
term of the contract and the scope of services to be performed. Any person seeking
exemption under this provision shall display such contract or affidavit when required
to do so by any law enforcement officer.