Dekalb and Asgrow RR starts at about $113. a unit which is 80,000 and will plant 3 acres, the way we plant population of 26-27000. One of the best inexpensive varieties is Fielders Choice for about $46. a bag of similar size, use what you need and save it for the next year, it will keep, germination might get knocked a very little, just plant thicker stand. Also Fielders is not RR, so cultivate it to keep the weeds ddown., and keep the weeds down you must. You cant grow two crops in the same space... (weeds and corn)