Process Yourself Or Take To Processor

I've day dreamed about the same thing. Building something inside a shop. Just a simple large box, spray foamed to desired R-value and put some kind of cooling unit in it.
 
Building your own walk in cooler doesn't have to be real expensive. You can insulate any garden shed or part of a garage and use a window AC unit.
There are several out there, here's an example.

http://www.storeitcold.com/howitworks.html
 
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