It’s possible to use Flex if you have a roommate(s) so long as your rent portal allows partial payments. If it does, Flex can submit a payment on your behalf for just your specific portion of the rent. Here's the process:

When signing up, you can specify the precise amount of your monthly base rent that you're responsible for. For example, if the total rent is $1000.00 and you're accountable for $500.00, while your roommate covers the other half, just enter $500.00 as your monthly base rent during the sign-up procedure.