Life in the balance

I should point out that once you have created equalibrium in your fridge freezer you just need to keep it that way. Any warm stuff going in has to have the heat removed, plus the heat leak into the box from the ambient. Think about it like water dripping into the bilge from a leaky shaft gland. You need to pump that water out otherwise you will eventually sink. If you insulate the fridge freezer well it is akin to stopping a water leak into the bilge and thus the fridge system will have less work to do. Like the Realtor told you Location Location Location!  

With fridges it's Insuation, Insulation, Insulation!