[cfhofer]

Derek/dgo71-

"I don't need an established market price to know the highest amount I'm willing to pay for an item"

You state you don't need market value to determine willingness to pay, but proceed to provide a market value example ($100) as a starting point...paying more ($120) or less ($80) depending on your needs. So you do use market value, whether you realize it or not. The two go very much hand-in-hand. Sometimes people disregard market value (or one isn't established) but we should take it into consideration when we buy anything (house, car, boat, gas, etc.), as your example illustrates. I'm willing to pay $10 for a ballpark beer, but I'm well aware I'm getting ripped off.

"There have been plenty such items that are not in my collection because someone else was willing to pay more than I was"

Sure, that happens to all of us. But there are some items I'm willing to pay 10% more than anyone else. What is that exact amount? I don't know but a healthy auction would determine that much better than a single snipe bid. In those instances, my final price point is determined by what everyone else is willing to pay for it.