This .dwg has 2 parking stall blocks with a field that will count the spaces. One will let the field text rotate with the block, the other keeps it right reading. There are 4 vis states and 2 stretch commands. One to increase the number of spaces, and one to increase the depth from 18' to 20' in increments of 6".
Credit goes to jnyazz since I modeled my block after his.