Questions about Managing Tours Attributes in booking form

Hi,
I’ve to manage your booking form introducing new attributes (times and language of guided tour) with different value for each day of calendar.
An external application will send, for each calendar day, and for different times and different languages the total number of tickets (Nt) available for the selected tour; then,
I’ve to check that the sum of number of adult and children selected in the booking form is minor or egual to this availiability.
How can I do? If it’s necessary a new development amd you are available for a quotation please send me your offer.
Thank you very much
Best regards
Chiara