I recently did a similar trip with my 82 year old mother, and a rental car out of Tampa. LOL...I get the same stubborness, but God Bless Her, she gets around pretty good. I do get her to use the wheelchairs at airports and cruises for the VIP treatment through security. I pulled the rental car up to the valet, and tipped him and told him that I would be back in under an hour. I went with my Mom on board through security, through check-in, pictures and on board in our room. Once Mom was settled, I went back out picked up the rental car, took it back, and took the shuttle back luggage free, back on the ship, all in about an hour and a half. Not for everyone, but worked for me.