Use a tablecloth on your prep table (either a disposable one or several sheets of foil). Makes cleanup so much easier.
Towels w/caribiners (golf towels).
Bring a pair of waterproof boots (if it doesn't rain, your neighbor will surely get carried away with the water hose).
Earplugs (count on your neighbors partying into the wee hours).
Life's a party with a Backwoods Party!