Here's an idea I just had. Sometimes I'd like to know how much it will cost to get to the next milestone for example, but I'm not one, ten, or a hundred purchases away, so I can't with the current buy amount buttons. Would it be difficult to implement a custom buy amount selector with controls for +- 1, +- 10, and +-100? I think it would be great to have more control over the cost of my next investment. =)
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