I was super lucky dude. This guy just happened to have three batches of 10 old packs the first day I checked into the site, and he was almost giving them away. I lost the auction for 10 japanese Neo Genesis packs, but I luckily won the other two. A week later, I found a batch of Base Set, and another of ex Rocket Returns, 10 packs each again. They were going for 15k yen each, 3x the price I paid for mine. It wasn't until then that I realized I should have gone harder for the Neo Genesis as well, but I was still thrilled with what I had.
I was also bidding on a sealed box of japanese Expedition, but the price grew from 10k to almost 40k yen, and there's currently an ex Series box going for 70k+. They have 20 packs in the box. Again, I was super. fucking. lucky.