[swarmee]

In a couple of groups, I bought approx 40 each of Oil Can, Whiten, Hoiles, 1990 John Morris, and two Topps Heritage cards with hard to see intentional errors. Out of the 300 I looked through, none were the valuable error cards. There were some of the purple and blue jersey of Whiten, and two of the common Oil Can Boyd variations.
I did only select sellers who had multiples of the cards I was looking for at the same time, and did discounted box shipping costs to make it at least reasonable for the treasure hunt. At the same time, I found about 10 cards listed around $10 each on Sportlots that I also purchased which I should be able to flip with a profit that will cover buying the other 300 cards.
Those larger dealers are probably the ones that are more likely to either have already found the errors *or* realized that I was purchasing cards for the chance at a variation and may have screened them before they mailed them to me. I also didn't buy any from the sellers that had over 8 of each card, figuring they would have also done what I was trying to do in the first place.

TLDR: It was fun once, but I probably won't do it again.