Feature request: Limit number of Guests (different from submission limit)

It would be great to have Form Maker stop accepting submissions once a certain "number of guest" has been reached? (Seperate from the submissions limit)

For example: On an RSVP form, guests can indicate the number of people who will be attending. For this example, let's say the event has only 30 seats at a venue. We need Form Maker to allow any number of submissions but to stop once the 30 seats are full. That could be 1 submission with 30 guests RSVP'ing or 15 submissions with 2 guests each or any combination therein.

In this feature, it'd also be great to be able to place a minimum and maximum number that each guest could possibly submit. (Example: a single submission could have a maximum of 5 guests.) That way, someone couldn't play a joke or accidentally fill-up an entire event.