This is a great concept!

One of the best ways to control your spending is to force yourself to use a mandatory waiting period before making any unnecessary purchases. Tell yourself that you will buy nothing until that waiting period is up. A waiting period gives you time to cool off, get away from the temptation, review your finances, and decide if you really, really want and can afford this thing that has you so captivated in the store. A waiting period can save you a lot of money (or time on the return lane when you decide to return the thing because you really didn’t want it anyway).

The Mandatory Waiting Period