I just made it to level 10 and have discovered this Bynum Brothers Broomworks that I've been hearing so much about.
38,000 BB cost, 30,000 BB on surge and 35,000 BB per cycle!
Can that be right? I've gone from having approx. 3,000 BB per cycle per asset to 35,000. I can't believe this isn't an error. These things can almost pay for themselves in a single cycle!