Bulk Price changes

I found this in a previous topic. # Bulk price reduction. It’s coming up on the end of the year and USPS shipping increases happen. I have most of my listings with free shipping. I need a fast way to increase prices to pay the increases in shipping. I found the apple script that @kristian talked about and tried it and it works! However, how are apple scripts stored for later use? Also, I would like to add a specific price ($.50) instead of a percentage. It would be nice to have this feature added to GS to increase or discount prices.