504 Modernization and Small Manufacturer Enhancement Act of 2020 This bill modifies the Small Business Administration (SBA) 504 Loan Program, which provides a small business with SBA financing—through a certified development company (CDC) intermediary—for expansion or modernization. Specifically, the bill adds policy goals, at least one of which a CDC must demonstrate to be eligible for assistance. These include (1) enhancing the ability of a small business to reduce costs by using energy efficient products and generating renewable energy, and (2) aiding the revitalization of any area for which a disaster has been declared or determined. The bill also authorizes a CDC to take specified actions to facilitate the closing of a 504 loan, such as correcting borrower or lender information on loan documents or reallocating up to 10% of the cost of a project, and it establishes an express loan closing program for a 504 loan that is less than $500,000. Further, the bill authorizes a CDC to refinance up to 100% of costs for expansion projects, and it establishes specified requirements for refinancing projects that do not involve expansion. The bill also modifies the requirements for projects to construct a new facility or to acquire, renoavate, or reconstruct an existing building. For small manufacturers, the bill (1) increases the maximum loan amount from $5.5 million to $6.5 million, (2) reduces the amount that they must contribute to project costs, (3) increases job retention requirements, and (4) revises collateral requirements. Further, each SBA district office must partner with a resource partner to provide certain training for small manufacturers.