The plan sets the baseline. Add-ons fill in what is missing — an extra number, credits, a plugin — without forcing you to change plan over a single feature.


These are things that vary a lot with usage: an account that runs campaigns every month burns through verifications another will never touch. Charging everyone the same would make the plan more expensive for those who do not need it.
Credits


The monthly package works out cheaperFor anyone using AI daily, the recurring package costs less per credit than the one-off — and it keeps the service from stopping on a Sunday because nobody was watching the balance.
Plugins

Calendar and Credit Management are examples: they are whole operations, useful to some customers. Those who do not use them do not pay — and those who do subscribe to that module alone.
On the invoice


- One-off — a single charge, it does not repeat.
- Monthly package — joins the recurring charge alongside the plan.
- Plugin — its own monthly fee for as long as it is active.
AI credits are the first to block youIf you rely on automated service, this is the balance that runs out before any other — and when it does, the AI stops replying mid-conversation. Worth switching on the low-balance alert and keeping a monthly package.