If you are going to be staying in a major resort hotel before or after heading out to Hana, all major resorts have a locked storage room you can check your excess luggage and receive a claim ticket for your bags, and then just take an overnighter with just what you need during your Hana drive, and pick up your other things when you get back. There is almost never a fee for doing this.

If you absolutely need your laptop on your overnighter, put it in the trunk, or like the other respondent said hidden under clothes or a blanket. I’m sure you would love pictures of swimming, but I would worry about my camera unattended so in the trunk it would go!

keep everything in the hotel safe–including cameras,e
Tc

For one, lock your car.

What my parents do is place a blanket over things that are stored in the backseat so nobody can see what they are.

As for camera safety, you can get one of those waterproof cases to keep the camera from getting wet.