If there are practical difficulties or unnecessary hardship in carrying out the strict letter of the Zoning Ordinance, the BZA may grant a variance in any of its rules or provisions relating to the construction, or structural changes in, equipment, or alteration of the buildings or structures, or the use of land, buildings, or structures, so that the spirit of the ordinance shall be observed, public safety secured, and substantial justice done. Submit the BZA Variance Application and appropriate fees.