We have a client who will be recording people who attend theatre productions. These attendances will be recorded as CRM activities (imported in bulk). The client would then like to search for people who have attended x activities (maybe over a set time period). Then group them and contact them.
CiviCRM would be very good at telling us who attended one or more theatre attendance activities. But not mutiple. Considered smart groups, custom searches, search builder, extended reports etc.
We think a custom extension may be needed for this. Any ideas would be appreciated.