Describe the lot as an empty field versus abandoned buildings. Specify if it is a corner lot, or contains a corner lot. Note anything else about the lot that is significant, what the "for sale" sign says, what it used to be, and/or if you happen to know who owns it.
Example: 9900 N. Garey - across from the hospital, one full block that contains a corner lot and abandoned buidlings. Available from real estate agent A at 909 909 9999. Used to be a hair salon.