On our first rig, a Starcraft autumn ridge, it had a storage compartment under the wardrobe in the bathroom that I just cut a hole thru the lower part so our 2 girls could access it. It was right there at the outside compartment door so I could just open it and take the box out to clean it. Our current rig is a Coleman 268rk with no other place to put it but under the end of the bed in the storage compartment there. Again, I cut a hole for access and we just lift the end of the bed to get to it. It works well. As to the smell, we really have no issues and I agree that the food might be the culprit there. Ours are very picky eaters and they seem to like the Purina one smart blend brand. All I can say is poop is poop and keep it cleaned out as much as you can.