Kory, if that would be the easiest for you, I envy your stash!! lol!!
You don't have to add products by entering the barcode numbers. That is only if the product is not already in the product database. It's faster to just make a search for the product. When you find it, click on it and you'll get to the page view where you click the box "In Stash" and it's on your stash list.
Until you get your iPhone in May, you could use the ScrapStash app for ink pads, mists, stickles and other products that are hard to remember if you have or not when you're in the store. I know that I always have a hard time remembering if I have a certain color of Glimmer mist or not. So it's great to bring these lists with you when shopping.