RE: Reserved Quantity within Inventory
You might be able to do a couple things:
If you have Bin Locations: Tell your purchasing agent when she opens the Item card not to look at the Quantity On Hand, but to instead go to the Navigate tab, and in the Warehouse area of the Navigate ribbon choose Bin Contents. This will open the Item Bin Contents window which will show how many of that item are still in the Bin(s) where it resides before it gets picked.
The other thing is, if you use Warehousing you should have setup a Bin location dedicated to Items that have been picked. For instance, in our system after an item gets registered for a Sales Order Pick it moves into a Bin called 'Shipping'. This makes it easy to determine how many have been picked for Shipping though they have not actually shipped yet.
Another option is to have your Purchasing agent use the Availability Status report. Use the search bar to search for it. Another option is to pull up the item in a Sales Order and to the right in the information box NAV will tell you how many of that item are currently available. You can also write a report that takes Quantity On Hand and deducts the amounts on Sales Order and on Production Order - giving you the Available balance.
Using Reservations is another topic. However, as soon as you create the pick for a Sales Order that item gets a soft reservation against it... and once the pick has been Registered then that item becomes reserved for that Sales Order.