"Anybody can go homeless. Everybody is one step away actually." Joe is one of tens of thousands of people taking advantage of a little-publicised Walmart policy that allows travellers to pull up in their car parks and stay the night for free. He has lived in the Walmart car park for the past seven years. Since the housing crisis began, makeshift Walmart communities are attracting Americans from all walks of life. With well over a million on the streets these car park shelters are rapidly being accepted by local authorities. "I'd rather have them in a Walmart parking lot than out by the side of the road or off the highway somewhere where they're not as well protected", says the mayor of Flagstaff, Arizona. Yet as the shelters become a permanent fixture, many are getting stuck in the system. "A lot of them are stuck now; they've gone through their resources", says social worker Richard Durfresne.

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