So we are for sure going with insulation now. We are in the assessing options phase now. We are looking at a temporary roof insulation of 1/2" foil backed styrofoam between the "ribs" of the ceiling and covering it with fabric for now. This ultimately leaves a small air gap between the foam and the ceiling. Initially I thought that there would be enough room for a layer of reflectix to go between the foam and the ceiling with an air gap but I was wrong, so its just the foam with the foil side up for now.
I think that we will be using something inside the wall spaces. We will be reusing some of the side plastics(not all) and on those pieces I think I will be gluing reflection to the inside of the panel since it will sit of the wall providing an air gap.
But.... for now I have run into other issues that will require our attention... I'll be posting a new question shortly =)
Homemade headliner - attached with extra strong magnets
head liner above future bed area
Foam before being cut