YITH Cost of Goods for WooCommerce allows you to check easily and quickly the real profit margin on the sale of your products.
By using it in combination with YITH WooCommerce Product Bundles, you can add a cost of goods to your bundle products.
After installing and activating both plugins, a new field will be added to the bundle option in the product edit page as shown in the image below. Here, you can enter the value expressed in your currency.
For further details about YITH WooCommerce Product Bundles settings, please refer to the official documentation.