Selling and pricing in full case quantities

Just checking to see what others have done?

All our pricing is done by price books (40 + price books, Page 1 only).
TODAY when someone order 47 boxes of XYZ they pay $1 per box (or a total of
$47).
What is the best way to go about automating a pricing strategy such that
TOMORROW we would could encourage customers to buy 1 FULL CASE (48 boxes)
at $47.04 ( $.98 per box) or a "2%" discount.  (It is yet to be determined
what happens when a customer sends in an order for 100 boxes ... 2 cases
plus 4 boxes).

This standard "2% " discount will apply to certain groups of customers and
certain products provided the line item is ordered using a CS (case) unit
of measure (rather than ordering individual boxes).  It is unlikely that
all the items on the order will be ordered in full case quantities.

Is this do-able with standard user exists?

Second, customer service takes phone orders, and we need some way to alert
a customer service person that the customer that is ordering 47 boxes, is
just one short of a full case.

Thanks

Roger Blocher
TECH International
I.S. Manager
740.966.8009
740.967.3583 (fax)