The equation given explains it pretty much as it is. The variables in the expenses area is a doozy at present, price of fuels, replacement costs on machinery, site licenses, your labour, many incidental, weather, bee sites . A few hundred boxes does not give you a significant income at the end of the process. A couple of thousand maens employing help. There is a paucity of profitable beeks due to these factors and others. Run a lean operation and you will covwr costs and have a self paying hobby. Good luck with your venture.