I didn't have room at home for a large suitcase to lay anywhere, but I do have a handy sized soft-sided ice-cooler. One that you can fold up and stash away when not in use. I laid a folded towel in the bottom for a little added insulation, laid the heater set on "LOW" on the towel. Note; NEVER fold a heating pad, the folded section will get VERY HOT and can possibly start a fire. This cooler was just the right size to stand 6 bags in on end. This made it very easy to pull out a warm bag and drop in a cool one out of the box.
My nurse had me use one of the dialysis solution boxes with the heating pad. The box with the flaps folded down was enough to hold in the heat. I left the heating pad on all the time until I started using the cycled.