Even interested in finding information regarding the pricing and discount rules?
The Price Report in SAP B1 can help you with it. To find Price Report, just go to the price field, right click and choose Price Report like below.
Here you may find the source of price and many other details you may need.
Price Report is a new tool in SAP B1 and can be found in the versions SAP B1 9.0 or newer one.