Someone suggested yesterday that if you have the space, a walk in refrigerator and a walk in freezer would be great.
Basically you use plenty of insulation (at least R-25) around the room and have an external source of cold air. Many people apparently use slightly modified air conditioners to cool their walk-in refrigerators. Generally you want the temperature to be anywhere from 35 to 40 F.
For the most part older refrigerators and freezers can be expensive to repair and hard to find parts, if you can find them at all. For many people, if the refrigerator or freezer quits, the answer is to buy a new one. With a walk in refrigerator, especially if you use a commercial air conditioner to cool it, you have more room to work on it or it can be repaired by your local air conditioning company, and if you need to replace it, the replacement is probably going to be less expensive than what a new refrigerator would cost.
You could probably have two cooling units in each for redundancy and still be cheaper than what a single refrigerator and freezer would cost.
You should be able to insulate it far better than a store bought unit as well. It should not be all that much more to use a walk-in refrigerator or freezer if you have enough insulation.
And talk about room. With a walk-in freezer, you would have room for an entire frozen side of beef. You could raise your own geese (outrageously expensive in the stores) and turkeys, butcher them for Thanksgiving or Chrismas months ahead of time, and keep them frozen and ready to go.
Do you do much hunting and fishing? You would have plenty of room to store everything in an organized manner for future consumption. You could have a wire rack with a box for catfish, a box for trout, and a box for bass. And storage for an entire deer or elk.
And plenty of room to dry age meats.
Need ice? You would have plenty of room to make all the ice you need. When I was a kid, we would cut the top of milk cartons, rinse them out, fill with water, and put in the freezer. A block of ice from one milk carton would keep a water jug cold for the morning. And another for the afternoon. On the farm as a kid, it was hard to keep enough ice to keep our water cold out on the tractors and combines.
One thing I do is keep my uncooked rice in the freezer to keep bugs from colonizing it. A 20 pound bag of Jasmine rice, a 20 pound bag of Basmati rice, and a 20 pound bag of brown rice takes up a lot of room in a freezer.
It's very easy to keep so much in a stand-alone freezer or refrigerator that it becomes difficult to find everything. A walk in freezer with wire racks and it would be easy to keep everything properly organized.