This sounds like a micro loan, are there interest rates? December 18, 2020 21:11 Updated Nope! Flex will pay your rent in full starting on the 1st of each month. Then you pay us back throughout the month! There are no interest rates or late fees! Just a monthly membership fee of $19.99. Related articles How do I qualify to use Flex? How does Flex work? If I sign up on the 1st of the month, will Flex cover my rent? What is the last day I can sign up for Flex and have my rent paid? I have roommates, can Flex cover only my portion of the rent? Comments 0 comments Please sign in to leave a comment.