Whether you should maintain the records yourself or transfer them to the State agency after a certain time period depends upon your individual contract.
If you maintain the records yourself, you are required to follow the same retention period and final disposition instructions that the State agency must follow.
To determine these, contact the Agency Records Coordinator (https://www.in.gov/iara/services-for-government/agency-records-and-forms-coordinators) for the agency with which you are contracted, and ask which Retention Schedule and Record Series (https://www.in.gov/iara/divisions/records-management/state-records-management/state-retention-schedules/) apply to the records you're working with.