One way to defeat this is to use a Buy-It-Now with Best Offer format, rather than an auction format on higher end items. Set the Buy It Now price a little over what the item should go for. When the offers start to come in, you might quickly accept a reasonable offer from a reputable eBayer. If you get a $1500 offer from someone with 0 feedback, you might contact that person to get a feel for whether they're a flake or not.
COMC auto accept is currently set at 35% off.