Geez. I used to complain because I have to heat my darkroom. Temp fluctuations here range from +40 TO -40c, with the majority in the lower end of the scale. My darkroom in the basement rarely gets above 20C even in hot weather. When it's -40C outside, the ambient temp in my darkroom is about 15C. No cockroaches here. Seems they don't like the cold.
Thanks again guys, the addition to my existing HVAC is not possible due to the way the people built the house. The "easy" part would be overcoming the joists running in the wrong direction. But there would be a lot to overcome. I am looking at a portable AC by none other then Sharp. Why Sharp? The reviews are pretty dang good including reviews on the very low noise level.
If you operate a small refrigerator in a space already cooled by A/C, the refrigerator will not have to run very much to cool its interior. Also, new refrigerators are much more efficient than older ones. Get a cheap new refrigerator in preference over an old junker, if you want to save money on electricity.
But, the air conditioner will! Remember, as much cold as the fridge produces inside itself, it makes more than that amount of heat which shoots out the back/bottom. Your going to spend most of your money on A/C to cool the heat produced.
I would choose one or the other. Do you really need both? Or, could you put your fridge just outside the door, where its not air conditioned.