NOTHING for Free and paying for most buildings with gold , but NOT FREE. Just wanted to update and add that they have a system in place where you must keep happiness high. You do this by balancing business with houses. Problem is, it is nearly impossible to do that. If a business needs 30 people, they set it up so you will gett 31 or 29 people, which causes people to leave your cities. This game is AWFUL. 1Star is too high.