Thanks for your response even though we still have not heard from anyone who has actually done this! Friends that have stayed on land in HI say that driving is no problem. I am still investigating other tour companies to check their rates with a driver...our problem is 10 people. NCL says they shuttle you to the rental place and then you have that day as long as you are in port to return the vehicle. There is no keeping the vehicle overnight. Good luck and let me know if you learn any more.