if you dont wanna waste a lot of money upgrading get 2 of the same towers like the banana farm and get enough money and then after you upgrade the first banana farm once quickly go to the second one(make sure their close to each other)and the second banana farm should skip the first upgrade and go to the second one also works on super monkeys so you can skip laser vision and go to plasma to save like 2800 bucks also if you do get it correctly dont click anything else or else it doesnt skip the upgrade
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