title: Buying upgrades using different accumulated numbers of points
body: <p>I am creating an incremental game like a cookie clicker... When the player has gained 20 points, they can buy a Super Click upgrade, which will then give them two points every time the button is clicked.  The next Super Click upgrade will cost 22 points, and give them 3 points per click. But in this case I manage to buy with 20 points, now it only buy the super click with 20 points continually but I want to switch to 22 points, What should do?... Thanks</p>