that's a brilliant resource.
I actually purchased the live calculator there for 3 gold. The free version is slightly outdated with market prices and exchanges rates but still very useful.
I've had 5 companies in my eRep life, 2 Q1 weapons, 1 Q2 weapons, 2 Q2 iron, out of which my Q1 and Q2 weapons was conqored and my 1 Q2 iron was unprofitable too run. The profits you'll make are very dependant on where your company is placed and what industry you're in. A weapons company is highly profitable in war times but a dip in market prices or a climb in market wages can severely affect one's profit. I make around 2.20 gold a day on my Q1 weapons company by means of purchasing cheap iron from my iron company. With a finished goods company, you'll generally make around 1+ gold a day and for a raw material company, sub 1 gold for Q1-Q2 and 1+ for Q3-Q5, etc.

