tbhaxor-subscription-setupfee

[sick canyon]

How are you creating subscriptions?

When working directly with the subscriptions API you can use add_invoice_items to put one-time payment items on the first invoice:
https://stripe.com/docs/api/subscriptions/create?lang=node#create_subscription-add_invoice_items

If you're using Checkout, your line_items can include both the recurring subscription prices and one-time prices representation setup fees:
https://stripe.com/docs/api/checkout/sessions/create?lang=node#create_checkout_session-line_items