The pricing of Topol plugin is based on the number of active users in a given month. 1 user corresponds to 1 UserId set in the plugin configuration:
authorize: { apiKey: "Your Api Key", userId: "User ID", },
Active users are enumerated and the amount is used for monthly billing purposes. Images and other files used in the template are associated with the UserId and they will not be visible to the other users. A user corresponds to one client of your app, CRM, ESP, etc. That means that if your application provides an option for teams and the team shares images and templates, it's 1 user for us.