Haw. Rev. Stat. § 431:10C-303.5: U-drive insurance policy; primary.

(a) A U-drive motor vehicle insurance policy shall be primary; provided that its bodily injury and property damage liability coverages shall be secondary to the operator's or renter's motor vehicle insurance policy if:

(1) The U-drive rental business provides any claimant or person sustaining accidental harm or damages, as a result of the operation of the rental vehicle, the identity and address of the operator or renter, along with any information available to the U-drive rental business as to the identity and address of any insurer under any liability policies applicable to the operator or renter; provided that the U-drive rental business shall make reasonable efforts to obtain such information;

(2) A suit may be filed and service upon the responsible operator or renter can be effectuated; and

(3) An insurer responds on behalf of the operator or renter to a claim or suit.

(b) In cases where the U-drive motor vehicle insurance policy is primary because of:

(1) A failure of a renter or operator to cooperate with the U-drive rental business in providing the information described in subsection (a)(1);

(2) The failure to file suit and effectuate service as described in subsection (a)(2); or

(3) The failure of an insurer to respond as described in subsection (a)(3) or defend a claim or pay required benefits or a judgment;

the U-drive rental business may recover from the renter, operator, or insurer, the sums the U-drive rental business expended in payments or benefits, along with reasonable attorneys' fees and expenses.