You are correct, for the small guy, ( buying less than 55 gal drums )
there is not much money to be made after all the taxes,
equipment,material,vent system,,electric,,, ebay ,,web site,,ect..
I have kept tract of every penny,, to the best I can,, electric & heat are hard to judge,,
For us small guys you need to just enjoy the hobby.
its a fun deal,
make a living no way..
pay your pouring bills -- maybe ?
Jeff