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# Add-on Price Setup (Extra Fee for Special Options)

You might want to add a small extra charge for certain customization options. For example, if a shopper picks **2 dogs** instead of **1 dog**, you can set up an additional fee inside Customix.

![Extra fee for specific option](https://storage.crisp.chat/users/helpdesk/website/-/b/3/c/1/b3c1fc6f21f6e800/image_1ccsu0u.png)
Here’s how you can do it:

# Step 1. Create an Extra Fee Product in Shopify
1. In your **Shopify Admin**, go to **Products** and click **Add product**.
2. Give it a name (for example: **Extra fee**).
3. Under **Variants**, create the option you want to charge for (like **2 dogs**).
4. Set the price you’d like to add.
5. Save the product.
![Create a extra product on Shopify product admin](https://storage.crisp.chat/users/helpdesk/website/-/b/3/c/1/b3c1fc6f21f6e800/image_1xl5sen.png)
# Step 2. Open the Template in Customix
1. Head over to your **Customix App backend**.
2. Open the template that’s linked to your product.
3. Switch to the **Option Sets** tab.

![Open the Option Sets tab](https://storage.crisp.chat/users/helpdesk/website/-/b/3/c/1/b3c1fc6f21f6e800/image_rn1kc3.png)
Step 3. Link the Add-on Price
1. Select the **Number of Dogs** option set.
2. Scroll down to **Add-on Price** and open it.
3. Click **Attach variants**.
4. Choose the **Extra fee product** you just created, then pick the correct variant (e.g., **2 dogs**).
5. Confirm, then **Save** and **Sync changes**.

![Link the option with the extra variant](https://storage.crisp.chat/users/helpdesk/website/-/b/3/c/1/b3c1fc6f21f6e800/image_fqjzgr.png)
# Step 4. Try It Out
* Visit your storefront, select **2 dogs**, and you’ll see the extra charge applied automatically.

That’s it! With this setup, your store will add the extra fee whenever customers select the special option.