I want to make everyone aware that if your rental car doors are unlocked, then your trunk can also be opened by simply popping a lever on the trunk handle. No keys needed!

This can be bad knews if you're stopped at an intersection. If your car doors are unlocked, then you don't need a key to get into the trunk. Someone could just walk up, open the trunk and take off with your stuff.

When you're driving, lock the car doors. This is a responsible move anyway, but I imagine that most people would not assume that the trunk is accesible (without a key) simply by having the doors unlocked.

Ok, point made. I'll stop being redundent and rambling.