Obviously there weren't any coins or you would of found them. This happens sometimes you will not always find what you're looking for. The garrett is a good machine, i bought the garrett at gold a few years ago and found 4 silver coins, sterling silver men's ring, many junk rings and over 120 dollars worth of coins the first couple of months i started.
Its great to have a mover on a large van but on that pitch it would have been far easier & quicker to have dropped that in there with the tow vehicle !!
@dandaman1881dg that is why you should only rev it, (that i if your an idiot using no weight on the machine) to the point where you just engage the clutch