Help Setting Up Inventory Sheet to be used with a Barcode Scanner

Greetings All,

I've seen several forums on here addressing the problem in various ways and they've been most helpful, but I've reached a block with a project that I am working on. I work in a small computer repair center for a larger organization. Throughout the day several workers form different departments may remove things from our small equipment inventory and we're looking for a simple and cheap way to track the quantity of each item. My goal was to have the following

1. Scan a SKU and if it already exists in inventory it will deduct 1 from the total count
2. If the item does not exists it prompts you to set the Product Description and a starting count for the quantity

I've managed to get goal number working with the help of some other forums, but I cannot for the life of me figure out how to do step 2. With how I currently set it up it adds the value, but overrides cell A2 and then copies the information from B2 into the next empty cell in column B.

I've attached a copy of my spreadsheet below. Any help would be greatly appreciated.

Thank you so much for the help. That definitely fixed my issue. I'm now trying to make it a bit more robust and was wondering if you could give insight into another issue that I want to address with the sheet. My next goal is to have certain categories of products (laptops, desktops, monitors, and printers) scan and update the product count (as it's already set to do), but also bring up a custom form that then outputs the information from the form to an Access database. For example when I scan the laptop SKU it allows me to update the count, but then also loads a form asking for the following:

1. Laptop Serial Number
2. Model
3. Owner (person entering the info)
4. The date
5. Any Comments

I should have no issue creating the form itself, but I have no idea if it's possible to push out the form results directly to access instead of having it make a sheet in excel and then just export it to Access. I also don't know if it's possible to have excel distinguish between SKUS that will need to load the form (I was originally thinking of adding in a simple yes/no box for the user to indicate if they need to use the form).