Cambro, among others, manufacture a line of military-grade Insulated Food Transport Container's. I have one that is designed to hold up to one one full-size hotel pan (or 2 half pans, etc.).
These can be found at a very reasonable price relative to restaurant-grade Cambros.
for more information:
PS: I also use ice chests when I don't need to hold food for so long.
Here's one I got of ebay for about $40