I've bought and sold a total of 725 items on ebay, and still have a 100% positive rating, though I've had to go to bat for myself a few times and also make a few adjustments on a mistake or two I've made. These were mostly small items, however.
I'd never buy a car or boat without seeing it myself or having someone (either a trusted friend, C-Brat, or professional) evaluate it for me before the bid or purchase, and for a a really big item, I'd go see it myself, if at all possible.
Joe. :teeth :thup