Hmm, that's a tough one, but I would go with the person who put the box down being at fault. Yes, I guess ideally the person should have looked behind the car before they backed out, but the one with the box should have thought about where they were putting the box and eliminated the possibility, but hey, hind sight IS 20/20, everyone makes silly mistakes from time to time.
Oh, and my guess is you shouldn't have put the box behind the SUV.
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Steve
'08 Boxster RS60 Spyder #0099/1960
- never named a car before, but this is Charlotte.
'88 targa
SOLD 2004 - gone but not forgotten