Date-sensitive inventory tracking??

Hi all!

I'm loving QB so far, I've been building a job/event management app with inventory tracking and I'm running into a bit of a wall. We're an event planning firm, and what we need to be able to do is this: upon creating an event (Event A, let's say), the inventory items used for that event need to be removed from our general inventory from the Setup date of Event A to the Tear Down date of Event A, AND when another event planner creates an event (Event B) during that same time period as Event A (or in an overlapping time period) they can only propose the number of inventory items left in stock minus the items proposed for event A. That way, no items are double booked. 

Any ideas? I have an inventory table and a pull list items (items reserved for an event, looks up to inventory items) table. 

Thanks in advance!!!