Once you have created a Quote and added products to it, you are able to edit certain sections of information directly from the 'Quote Lines' section.
Step 1: Navigate to the Product section
Within a Quote, navigate to the Product's section. In the top right corner of the Product's section, select the 'cog' icon, for settings.
Clicking on the cog icon will open the settings options shown below.
It is then simply a case of selecting which options you want to be editable.
You will now be able to edit those values from the 'Quote Line' section.