When we contacted St. Augustine's A1 Used Truck & Auto parts inquiring about a shoot, they seemed a bit skeptical—I mean, common, having a photographer and model run around where cars, tires and oiled machinery are in piles. Definite liability.
BUT in the end, we had a pleasant tour guide who painlessly watched the photo process and we got to stay past closing time. I showed one of the guys some of the shots on the back of the camera and he smiled, "Ah, one of them gonna go on the wall inside."
Lesson learned for on-location shooting: It never hurts to ask.