You can go back and play levels (1 and 2 are the fastest) to get more money to upgrade the buildings - it's a grind, but seems to be the only real way; once a goal is met (i.e. build 6 cabins), it seems that you can then knock down those cabins to try to meet another goal - that's the only way I passed the ice rink level; some levels seem unpassable until several upgrades have been made in the Build menu; REALLY needs a Why the Hell is this Building Empty? button
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 "Ski Resort Mogul"){kind=icon}