RentCafe pulls rent amounts from the unit setup. When you add units to a property, enter the market rent for each unit, not the current rent paid by a tenant, so that RentCafe will show the correct amount.
If there are multiple vacant units of the same type (for example, one-bedroom, one-bath), and their market rent is different, RentCafe will show a rent range for the units (for example, 1500-1700).