I buy materials for customers jobs and put 30% markup. The materials I buy are almost the same for each project. I would like to create a list of all materials?

create a purchase order with the listing, memorize is and use it over and over

Hi there,  

Do you mean a bill of materials (or product recipe)? Because unfortunately, QBO doesn't have that feature. However, there is inventory management software on the QuickBooks app store which can do that for you! Like Katana, it’s a piece of inventory management software that helps you with stock control, saving product recipes, production scheduling, floor-level management, managing multiple sales channels across different locations and order fulfillment.