Some graffiti is artfull and seems worth the time taken to both do and admire, but when some tagger just scribbles an incoherent string of characters along your fence or rock wall it makes you wish you'd been hiding in the bushes so that you could throttle the little darling.
your Municipality has instituted a Spray-bomb distribution program where registered graffiti artists receive several cans of paint with a wide array of colors for free. Empty cans are returned for exchange.
The paint contains uv sensitive pigment which cause the "work of art" to fade within a couple of weeks direct exposure to sunlight.
With guests coming you don't have two weeks to wait so a quick jaunt to the Graffiti exchange office lets you sign out a strong portable uv lamp which acts as an eraser.