In a nutshell: Bags are one time use. Cost $0.07-0.09 cents per bushel to purchase. Unloading is done with a specialized extraction machine utilizing augers and a hydraulic powered roller that winches the machine through the bag. I bought my equipment 4-6 years ago and haven't priced it since. At that time you could get into a decent used setup of bagger and extractor for $50-60K. | 
Grain bagging
