You haven't SEEN a garage sale till you see one in this town. I would never put one on, but my neighbors (in violation of the law which limits them to 2 per year) have them once or twice a month.
They come from 50 miles away, Mexican families from Watsonville and Los Banos and Soledad and Gonzalez and Chualar and Aromas and from the crime-ridden East side, in Chevy Astro vans and Nissan Quest vans and Ford Aerostar vans and vans that you can't even tell what they started out as. They disgorge a dozen folks each and they descend like locusts, and then they park the vans three deep on the street. Forget driving up and down your street for the morning, the streets are literally impassable, and forget even getting out of your driveway. They won't move an inch, and "no se!" and "no habla!" is all you'll get if you ask, and everyone pretends they have no idea whose three vans are parked right on your driveway, leaking oil and tranny fluid and ancient coolant all over everything. No point trying to go out and get the newspaper, as it's been stolen by 6 am. anyway.
As soon as they hit the street the garbage starts piling up. Fast food wrappers, soda cans and garbage of all kinds and description. They lay their kids down on your lawn or the hood of your car, change them, and then throw the crappy diapers into your bushes and flowers or under your car. The mothers take the young kids into the street, where they squat to pee, or stand and pee on the rear wheel of your car. Pets are run over or stolen, and my wife keeps her pure-bred Chihuahua practically strapped to her while the "sale" is going on. A dog like that is cash on the hoof so to speak.
Usually about half the garage sale table items are swiped either covertly or by snatch and grab & run like hell. If the neighbors leave their table to chase the theives, then the rest of their stuff will get stolen immediately, so they have to work in teams.
My gates are opened, flowers are cut, and my garbage and recycle bins are gone through, with the trash dumped all over the ground. As someone else mentioned, I NEVER open my garage door or leave the car unlocked, or they will strip it bare.
Now when I see the dozen ugly ripped cardboard signs taped all over the neighborhood warning of the next days onslaught, I park my car in the street facing outwards, and hammer two stakes into the ground on each side of my property line, and then stretch "police line do not cross" tape across them. Then I stand up in my loft overlooking the street with a megaphone and yell down at them while they are trashing my house, or blocking my driveway and tell them to move _before_ they get out of the van and get lost in the crowd.
After a couple of hours, or if I really have to leave, I'll call the cops to clear a pathway through the wrecking yard of junker vans, and then usually spend the next day trying to clean up.
There's something to be said for living out in the sticks...!
Norm