Question: handling resources without delete


I have a question and would like to know whether there are best practices for resource that don’t have delete functionality.
We’re developing the Terraform provider (CloudSigma). Some functionalities in the cloud can be purchased as subscription (e.g. static IP address). Subscriptions cannot be deleted, they just expire (or can be auto-renewed).
My question is: what is the best practice to implement it into Terraform provider?
Is it something what an user should take care about and use prevent_destroy = true. I can imagine that if the user run terraform apply/destroy multiple time, he creates a new subscription everytime and this is not the behavior what he expects.

I’m happy to hear every suggestions/ideas or take a look on other providers (but I didn’t found similar things).