How to change "Item", "Quantity" and "Cost" titles?

Hi Jared Ch
You could change text string with many ways.
The easiest method is to install Codestyling plugin and then translate the desirable string to your liking.
https://www.ads-software.com/plugins/codestyling-localization/

Second, if the string cannot be translated, you could override the function which responsible for the string.
https://www.ads-software.com/support/topic/how-to-override-a-function?replies=17

Hope that helps.

Very helpful, thanks a lot ccov.

Hello ccov,

thank you for your help =)