Due Diligence for FEMA Disaster Contractors Act of 2018 This bill directs the Federal Emergency Management Agency (FEMA), before awarding a covered contract (i.e., a contract for goods or services, awarded in response to a major disaster or emergency, and in an amount that equals or exceeds $1 million) to: (1) conduct a review of the potential contractor, and (2) determine whether the past performance and resources of the contractor are adequate for the contract's performance. In carrying out such review, FEMA shall assess the past experience and resources of the potential contractor using specified criteria. FEMA may waive requirements of this bill upon determining that the waiver is in the public interest.