Hello Silvia, 

Thank you for your purchase. 

Unfortunately, there isn't such option in Amelia with its current built-in features and there are no hooks for actions or filters for that matter in Amelia. There are a few JS hooks which are triggered depending on the view:

window.beforeAddToCalendarLoaded()
window.beforeBookingLoaded()
window.beforeSearchLoaded()
window.beforeSearchFiltered()
window.afterSearchFiltered()
window.beforeConfirmedBooking()
window.beforeCatalogLoaded()
window.afterSelectCatalogCategory(object_category)
window.beforeCatalogCategoryLoaded(object_category)
window.beforeCatalogServiceLoaded(object_category, object_service)
window.afterSearchActivateService(object_appointment, object_serviceActive)
window.afterSearchGoToSecondStep(object_appointment, object_serviceActive)
window.afterBookingSelectDateAndTime(object_appointment, object_serviceId, object_providerId, object_locationId)
window.afterBookingSelectService(object_appointment, object_serviceId, object_providerId, object_locationId)
window.beforeConfirmBookingLoaded(object_appointment, object_service, object_provider, object_location)
window.afterConfirmBooking(object_appointment, object_service, object_provider, object_location)

If you have any further questions feel free to ask.