I bought the Talos Expansion back when it was P2P, was worth it. Would do it again on a sequel with the same mechanics. Came back and set the top survival score on my first run, love this game.
The cheaper ones grow in price far more exponentially, so becoming more costly than the more benficial investments, except for lemonade stands which are 69.618 septillion for my 861st.
Actually if you play it for long enough, newspapers do begin to cost more than anything else. 114.100 septillion for my 401st newspaper, 12.690 septillion for my 501st oil derrick. I've been getting up to octillions so far.
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