Looks like that seller did a wholesale order of 10 which discounts the price to $60, he sold 4 so far, has 5 left, thus is keeping one for himself.
In all, he paid $65 a pop with S/H times 10. Figure in $5 for S/H at $70 to future buyers, so I'd say go for a $76 - $80 Make Offer range if you're interested. He'll want to at least make $6 or more in profit. He limited his max to $84 with S/H as that's the same price you can buy it from krik's store individually.
Fair reminder though, krik will release V2 of TurboEverdrive in a couple of months, so I'd wait for that instead to see what new features he'll add besides faster loading times.