Solution is here…for every problem you encounter…there is a high chance that someone else encountered it too!
Once you get the Number of Days, you need another numeric field called Rental. Update Booking record, Rental field with a “New Formula”.
The New Formula option can be found when you select the Magic Text icon in the “Rental” field. You should scroll all the way down…
The math is INT(“Date Picker 2” -“Date PIcker 1”)x"Rental Rate"
The INT rounds down if you have a fraction of a day. The “INT” can be found in “Functions”…all the way to the bottom of the options available for numeric fields
This should do it…