I bought a lego expert creator brick bank before they retired it at $150 back in 2018 i think it was. It is now over $700. I also have the lego ideas fishing shack for $150 now around $600, and a lego creator corner garage at $150 now around $400. This one is not doing to well. Ebay/amazon take about 13% of what you make. At these prices you can sell shorter than other sellers and make your money back then some. Up to you to charge for shipping or pay it as an expense. Can buy items before retiring instead of release since they stay on the market for a good amount of time. $150 items, star wars items (especially the sets over $500), harry potter, avatar might be big. They just came out with fast and furious cars. There are videos of people doing this on youtube with storage spaces filled with boxes to sell. Im sort of new at it, but its a good extra income if you have found yourself on an income plateau. Other people antique which seems to require much more research, and less waiting since the product is already old.