user Permission Setup


For our premium service level we require some user permissions for your Inventory Lab and Seller Central accounts.

This allows us to print labels and create shipments on your behalf. We can not use Supply Chain Connect for premium. We do not list products through Seller Central due to it’s inefficiency. First, please read through all of these instructions and feel free to ask us any questions you may have before starting as some tasks are time sensitive.

Step 1: Setup Inventory Lab Permissions

Share “listing access” in InventoryLab by simply adding a sub-account with list-only privileges. This allows us to create new shipment batches, label items quickly, and upload shipments and box content information to Seller Central. NOTE: InventoryLab only allows one seller account per email login. We don’t have an email you can use, so you will have to create one of your own if you don’t already have a second email account to use for the sub account.

If you already have an InventoryLab sub-account for prep centers that you want us to use, please email us the username and password for it to and skip to Step 2: Setup Seller Central below. Otherwise follow these steps to create your own sub account for us to use:

1. To begin, you may either create a new email account (with Gmail for example) or use a second already existing email account of yours to be used exclusively for sub-account access to InventoryLab. We do not need access to this email account and it is only tied to your seller account.

2. Next, create an InventoryLab sub-account by following this guide: Use the email account you chose in the prior step for this account.

3. Add this email account as an InventoryLab employee: Check the box “List” under Inventory Lab (top-right of screen) > My Account > Employees > Edit. Go into the email account and click the activation link. Enter the password you’d like to use. You may then add our street address with your Amazon store name to your Ship From address: Inventory Lab (top-right of the screen) > Settings > Shipping Information > “+ Add” button. Our address is available in your client portal on our site along with additional instructions and tips.

4. Email us at with the sub account’s username and password.

Step 2: Setup Seller Central

You’ll need to give us access to ship by granting us Seller Central sub-account access. Amazon’s Seller University user permission video can be found here:

1. In Seller Central, hover over “Settings” (found at top-right of the screen) then in the drop down menu click “User Permissions”.

2. Under “Add a New Seller Central User“, add the email “” and click “Send invitation“.

3. We will accept the invitation email from Amazon as soon as we can and email you afterward. We usually try the Inventory Lab username and password you sent us at this time too. After we accept the invitation you will be able to select the level of permissions granted.

4. To add user permissions, log back into Seller Central and go to User Permissions (hover over “Settings” then in the drop-down menu click “User Permissions”.

5. Click “Manage Permissions” for Prep Ninjas. Under the Inventory section, change the buttons to “View & Edit” for “Manage FBA Inventory / Shipments”, “Manage Inventory/Add a Product“, and “Upload Inventory” then click “Continue” at the bottom of the page to save.

Step 3: Verification

We will ensure we have access to each account and let you know if we run into any trouble or if all went well. We will then be set and ready to process products and you can start sending products for us to process.

Day to Day:

Once you’ve made an order that is shipping to us, input the information about the order in your Prep Sheet (accessible through your client portal). We can discuss using a different system if you have one. We need to know what we received is what you ordered and how you want it listed and additional instructions if needed. Failing to enter the information for a product will delay it from being processed and may incur storage fees.

To maximize our efficiency, we process the packages we receive in batches. This means we may not update your prep sheet the same day we receive your package. We work through our clients on a rotation. When it is your turn, we will start processing the products we received by inputting the date and quantity they were delivered to us (Date Delivered) and mark the items as received. If we encounter any incorrect or damaged merchandise, we will take pictures and notify you immediately so you can contact the supplier. You may have to process returns and refunds yourself because we won’t have access to your accounts with the retailers. Most retailers make it difficult to impossible for anyone other than the buyer to return items. We’ll finish up the process by prepping and labeling your products, packing the boxes, and sending everything to Amazon. Afterwards we’ll note the shipment name and quantity shipped for each item on your prep sheet in that batch.

We try to optimize your shipping costs by waiting until there is a sufficient amount of product on hand, which is at least enough to fill a fair sized box as the main shipment. If we know there is nothing coming within a short time frame, then we will process and send what we have. Our goal is to fully process the shipments within 5 business days of the first item arriving.

We also recommend using all Amazon barcode labeling instead of using manufacturer barcodes. New seller accounts are set to use manufacturer barcodes by default. You can change that by following this tutorial: Using manufacturer barcodes allows Amazon to send what should be the same product you sold from the closest warehouse to the customer, even though it’s not the actual product we sent. However that raises risk that your customer could get a bad product sent by another seller. The units could be lost or refused at Amazon if the UPC/ISBN don’t match the listing. We cannot guarantee our work on commingled products if they aren’t the same units we are sending in.

If you have any problems or questions along the way, please feel free to email us at or use the chat on our site. You can call or text us at +1(541)514-8394 during business hours (9a to 4:30p US Pacific Time). We also highly recommend you go through the Seller University in your Amazon Seller account if you haven’t already.