What is the difference between these two? I can't really see if they affect anything by switching between the two.

I use purchase orders to buy material that is consumed on a job. I do not bill the customer for materials or resell them. I'm going through all of this and trying to get everything setup properly.

Searching here and online there is no way to have the billable item default to unchecked? So every time I enter a bill using items i have to manually uncheck each item? Not a huge deal but annoying.

What is the best way to set these items up for a business like mine that purchases items for a specific job but does not bill the customer for them?