Confusing, huh? If you don't understand this, try thinking about it this way. Take a $100 product and add 30% to get a selling price of $130. If you take that selling price of $130 and subtract 30% thinking you are going to end up with your cost price, you are wrong - $130 subtract 30% equals $91, not $100.

Now that you understand that, recall that the price mark-up difference between the auto parts store cost price and its retail price is about 35%. In other words, they multiply their cost price by 1.54 which is a 50% increase in price, but only a 35% mark-up.

I will explain the simplest and easiest way to get 20% off every part you buy from the auto parts store. As explained above, auto parts stores work on very large profit margins. You can use this to your advantage