Cashier pricing with number of licenses

Hello,

I am working on a SaaS product for a client. They have packages that contain a certain number of licenses.

They also want the facility for customers to add licenses manually.

I searched over docs, and there is no such way to create packages of that kind with either Stripe or Cashier. So, I am thinking of adding a model for packages that will contain package info, including the number of licenses.

Is there any better approach, maybe utilizing Stripe product metadata?