We use a wide variety of special characters for price levels. So far, no ill effects have been seen.

As an aside, we had a terrible time with ad-hoc assignment of price levels. Finally we scrapped them all and set up a standard grid, 1-9 means 1%-9%, A-I means -1 through -9%, then the alphabet sequentially 10-26% and then all the special chars have assigned discount levels. An Access program sets all those up whether they're needed or not whenever a new product line is set up, and we make only one price code per product line. It eliminated a lot of confusion.

Thank Jim, I appreciate you taking the time to share your experience with special characters. and then going the extra mile by sharing some of your naming to discount conventions. It looks like we are good to go with the special characters.  Thanks again.