These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
YMMV: American Pickers
Ron the Death Eater: Mike and Frank have been the target of much vitriol over the way they buy items for pennies and sell them for a profit, sometimes for way much more than what they bought it for.
On the other hand, there have been times when they step up and give a seller more than what they asked for because they know it's worth more and it's the fair thing to do. It should also be noted that, often, the price seen on screen is what they will ask for it. That price actually leaves room for haggling when they sell it, so what's seen onscreen is not necessarily what they'll get for it.
There's a case in the "Heartwarming" section where Mike and Frank found out how much more an item was worth than they had originally estimated. After the person who appraised the items decided to purchase them himself, they went back to the original seller and gave him some of the extra profit so he could use it to help rebuild an amusement park he owns that had been damaged by a flood.