This is the way to use EPA to update quantity, price or any other field for that matter:

It is a three stage process:

Stage 1.
* Do a EPA export

Stage 2.
* Open the exported file in Excel or your favorite spreadsheet software.

* Make changes to the appropritate field.
* PLEASE DO NOT ALTER PRODUCT ID FIELD. This is the field that will tell EPA how to match to corresponding products on your site.
* Safe your modified file as tab limited file

Stage 3.
* Do EPA import.

The same process applies to EPB. In EPB case DO NOT ALTER PRODUCT MODEL FIELD

delete is the only value currently programmed for v_action. If needed, custom programming can be done to allow other values.