The words "modification" and "addition" include, but are not
limited to, any alteration, addition, modification, structural repair,
rebuilding or replacement of any such existing use, structure or accessory
structure or use. Maintenance is not considered a modification; this
includes painting, decorating, paneling and other nonstructural components
and the maintenance, repair or replacement of existing private sewage
or water supply systems or connections to public utilities. Any costs
associated with the repair of a damaged structure are not considered
maintenance.