I was in a similar situation........I have a Jeep Grand Cherokee and it didn't have a tow package so I would put the rear seats down and then put a tarp down in the back, the deer would usually only be in there for an hour at most. Except there were a few times last year where I would pop a doe for a friend that wanted the meat, and I would leave it in the Jeep over night since it was cold enough, they would come over the next morning and drive the Jeep to the butchers. I also cut some pine saplings and leave them in there for the smell, but I usually do that anyway just for scent control. The only problem I had was that I would invariably get blood on the rear bumper when putting one in or taking one out....but it's a '98 and basically just for hunting these days so my wife has no cause to complain....now if it was her Mercedes...forget it. I finally ordered a hitch from JC Whitney for about $120, if you get the custom fit they install easy (6 bolts), I didn't mess with installing the eletrical connections but will some day....then got one of those cargo platforms that fit into the hitch...everything was under $200.