Specifics, all right.

A CurrentCash variable, it will be updated constantly to reflect the player's amount of money.

An InBank variable, it will be used to keep track of how much money the player has deposited into the bank.

And the Withdraw and Deposit variables, they will be checked with the other variables to make sure that you aren't withdrawing 1,000,000 gold, when the bank only has 25, or that you aren't depositing 50,000 gold, when you only have 60.

I took those directly from Draco2003's post

And also input keys, & deep into the structure of conditional branches in the RPG Maker 2000 & 2003. And could you explain global positioning a bit clearer and deeper.