I will now give you a simple rule to follow and a few questions to ask yourself before making any purchase. The first rule I learned straight from the mouth of Barry Schwartz during a guest lecture at the University of Pennsylvania (my alma mater). Barry is an economist that studies decision making theory and has a wonderful book called The Paradox of Choice.
Most things you will not still want to purchase after two weeks have passed, or, you will find a free or better way to do things. This gets rid of your initial feeling (compulsion) to buy and gives you more time to critically THINK about whether or not it is a good purchase. Try doing this at the department store, grocery store, etc. You will be surprised at how much junk you buy on impulse.
If you still want to purchase the product after two weeks, then ask yourself the following three questions:1. Will this save me more time than it costs to pay for it?
2. Will I actually use the product enough to justify the cost?
3. Do I have time to use the product enough to justify the cost? I will now discuss each point individually.