The version I bought was free, but comes with a north east factory that you have to cover the running costs for a full year, and top up the pension fund.
This game is weird. I'll not even think of it for 2 months, and then get a sudden urge and play until 3am. My crude oil => various chemicals production area now looks like some odd Escher drawing with looping pipes, strange chains of storage tanks and areas you can't reach.