Aluminum Thickness

We are in the process of fitting out a 4'x6' trailer to hold equipment for our Community Emergency Response Team. The shell will be the standard 4' high made out of 1/2" plywood. We want to cover it in shiny aluminum sheeting. We are a part of a large healthcare organization and will be "showing it off" quite a bit.
I know this has been covered in many posts ad nausium, however I have not been able to find it.
What thickness of aluminum do most of you use to cover the exterior ?
Have located several sources, but of course, there are numerous thicknesses. Thank you in advance for your help.
Bob Hall N5VCU
Security Manager
Patriots Colony at Williamsburg
Williamsburg, VA
I know this has been covered in many posts ad nausium, however I have not been able to find it.
What thickness of aluminum do most of you use to cover the exterior ?
Have located several sources, but of course, there are numerous thicknesses. Thank you in advance for your help.
Bob Hall N5VCU
Security Manager
Patriots Colony at Williamsburg
Williamsburg, VA