Subscriptions and plans: sell a tool alone or inside a plan, and the system delivers, renews and reminds
Build plans from the catalog's tools with monthly or yearly pricing and set a device limit per plan. The customer buys a single tool, a plan, or a custom plan they assemble themselves, and subscriptions stack with clear logic: single tools add up, a plan replaces them. Delivery is automatic right after payment, and so are expiry reminders and renewals.