Nordica COD Rules & Fee

Cash on delivery, under control, by Variegata Nordica.

Hide cash on delivery on risky orders: big orders, first-time customers, some postcodes.
Charge a fee for cash on delivery.
Also hide, rename or reorder other payment and delivery options.
Rules by country, cart value, weight, products, collections, tags and customer tags.
Runs inside Shopify’s checkout: no code in your theme, no speed cost.

Install it from the Shopify App Store, then open it from Apps in your Shopify admin.