How much does Flex cost me? November 21, 2019 18:21 Updated Our membership fees start at $14.99/month. This charge is taken on the same day as your final monthly payment. Related articles How does Flex work? When will my rent get paid? I finished signing up. Will my rent get paid? My property isn't listed. What should I do? What banks does Flex work with? Comments 0 comments Article is closed for comments.