THIS IS IN ADDITION To Ozk4r123's comment:
On Feb. 24, 2014 he wrote:
I hope this help a lot of people. I found that if you max a turret and sell it you make more money that it cost. So when u have the money to upgrade any tower to 5 do it, sell it, buy it, upgrade it, sell it, and again, and again. I did the last level with all my turrets lvl 5(rockets and lasers) +1 keep this comment alive.
In addition:
To start this method u need at least $6.100
$100 dollar turret gives $450 extra (Need $6.100)
$400 dollar turret gives $600 extra (Need $12.400)
$1000 dollar turret gives $500 extra (Need 31.000)
$2000 dollar turret gives !$3000! extra (Need 62.000)
$4000 dollar turret gives !!$6000!! extra (Need 124.000)
There is logic in prices, not in money back guarantee xD
So i was like, yeah i'm gonna go collect all them starts! But at the end.. that last star.. i can't get my eyes to focus enough to find one damn star, i guess
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