Lev finally reached his goal of $120 in his bank account, which would cover him for his Republic Gunship. He has, however, come to the realization that if he bought it, he would have no money left.
So he changed his goal to $200 to provide him with a sizeable remaining reserve after spending his money on the gunship. Now that he has reached $190, he is worried that it is not a big enough cushion, so his new goal is $300.
If he keeps this up long enough, I think he might give up the gunship and want to buy a Hummer.