Thank you. So would it be possible to create a data field that calculates the number of days based on the start and end dates?

I basically want the figure out how to calculate a total based on the entries

number of days
number of pets
any special options or needs, etc

for example
If I had departure date: (12/21/2017) based on their entry
return date: (12/25/2017) based on their entry
total: 4 days (calculated based on their input in previous two fields)

Eventually I would add the other elements