Upon request of the Department, a residential owner who applied for reimbursement from the Fund shall submit records that document all costs incurred and monies reimbursed to date for a site rehabilitation within: 6 months of completing the site rehabilitation; or 3 years of receiving the final payment from the reimbursement allocation. The Department reserves the right to audit all costs, expenses, or files associated with the Fund. A residential owner shall maintain all records associated with a site rehabilitation for at least 3 years after the later of: Receiving the final payment from the reimbursement allocation; or Completion of the site rehabilitation. If an audit reveals any amount of money was improperly paid from the Fund to a residential owner, the residential owner shall return that amount to the Department within 30 days of notification by the Department of the improper payment from the Fund. A residential owner is liable for any expenses incurred by the Department in collecting money owed under §D of this regulation.