Most people that make 30 bil a day are usually attack builds that cycle or skim units doing 1 hour haunts and hitting most of the items. At that point they start Allie trading to get a lot more money.
30b a day as a hansel no problem. Farming for extra on top of that just for laughs Haunting is the answer, pref 2 1/2 hrs long Hope that helps
I make 50 to 55 bil a day just doing epics. Throw in a couple ally trades can make upwards of 60 plus a day.