As a landlord, when adding a property (or under "edit rent" for any existing property) you can select "enable split payments". This will allow each tenant to pay a custom amount they specify towards a rent invoice.
For example, if you have "123 Main Street" with rent of $1200 due, Tenant A can pay $700 and Tenant B can pay $500 towards the invoice.
Note: We recommend thinking about properties as analogous to leases. We only recommend turning this on for properties with a single signed lease. If you have a property with multiple leases, we recommend adding each individual lease as a separate property (i.e. "123 Main Street - Tenant A", "123 Main Street Tenant B", etc.).