I have a home built refrigerator that I have adapted with a variable temperature controller and sensor . I have used it for lagering homemade beer, but it would be useful for refrigeration of anything that needs to be cooled at a specific temperature. The cooling coils are located on the inside of a 30 gallon plastic trash can, which is insulated on the outside. The unit sits on a wood frame with wheels. It isn’t pretty, but it works well.